Moreover, the results of experimental research clearly indicate that we shall never possess the means by which a mother may control the sex of her child. In the main laboratory investigations have sought to answer two questions. First, at what time is the sex of the offspring determined? and, second, what accounts for the origin of a male in one instance and of a female in another? The study of these problems has been carried on chiefly in connection with insects, worms, and fowl; but as yet insurmountable difficulties have prevented similar investigations in higher animals. For this reason, it is not without the greatest caution that results thus far obtained may be assumed to apply to man.

Sufficient facts, however, have been collected to admit no doubt regarding the answer to the first question. In most animals it is definitely known that the sex of the offspring has been fixed when the male cell enters the female cell, in other words, at the instant the ovum is fertilized. Excellent reasons exist for believing that human beings conform to this rule, and that the sex of the child is unalterably determined at the moment conception occurs. Consequently, any attempt to influence it after that event must prove futile.

For the present, the second question cannot be answered with equal assurance. More than five hundred theories have been offered to explain the relation of sex; nearly all of them have no reasonable foundation and are only of historical interest. The view that girls are derived from the right ovary, boys from the left, has long since been disproven, and deserves mention merely because the laity still believe it. Happily, during the last few years, observations and experiments have been made which greatly advance our knowledge of the subject and give promise of an early solution of the problem. The controlling factor in sex determination has been narrowed down to three possibilities; it is inherited either from the single cell contributed by the father or from the single cell contributed by the mother, or it is determined by the effect these two cells have upon each other at the moment when they unite. In most animal species the weight of authority distinctly favors placing the whole responsibility upon the male cell.

According to recent evidence, there are two kinds of male germinal cells; one kind giving rise to female offspring and the other to male. In all probability, at the time of the marital relation, these varieties are deposited in the vagina in equal numbers; and, moreover, the mode of their production is such as to place absolutely beyond human control the possibility of changing this ratio. Since only one spermatozoon enters the ovum, whether or not the child will be a boy or a girl depends entirely upon which type gains entrance. If this explanation is correct, and it is in accord with careful biological observations, it removes from the mother all responsibility for the sex of her child. Furthermore, since the facts indicate that male-producing and female-producing spermatozoa are present in equal numbers, it follows that practically there is an even chance that an embryo will develop into a boy or a girl.

Birth statistics bear out this conclusion, as data gathered from many countries indicate that when long periods of time are studied 105 boys are born with a surprising regularity for every 100 girls. Thus, the records of Berlin, Germany, for a hundred years show that the maximum difference occurred in 1820, when the males outnumbered the females by 4.79 per cent.; the minimum difference, which was noted in 1835, was .64 per cent. in favor of boys.

No inquiry is more often submitted to the physician by prospective mothers than this, "Can you tell me if my baby will be a boy or a girl?" He cannot. Many rules, to be sure, have been advocated as safe guides toward reaching the correct answer; every midwife possesses her individual formula which she has "never known to fail." But the boastful success depends upon the application of some such method as the following, which I have heard my teacher, Dr. J. Whitridge Williams, expose to his classes. The patient is asked if a boy or girl is desired. She confesses, and is then informed that the sex of her child will be the opposite of her wish. When this guess proves to be correct, there is no doubt of the prophet's wisdom; when it is not, his honor is protected, for the parents have had their hope fulfilled. Their happiness makes them forgetful that the guess was wrong, or, for that matter, that it was ever made.

It was once believed that the sexes might be distinguished before birth by the number of heart beats occurring within a minute. In a general way, the action of this organ in females is somewhat more rapid than in males; and so it was thought that a rate of 144 or more indicated the female and a rate of 124 or less the male sex. But experience has taught that this rule leads to accurate prophecy in no more than half of the cases. As a matter of fact, no means of definitely foretelling the sex of the child has been discovered, and I doubt if it ever can be.

TWINS.—As every one knows, pregnancy commonly terminates with the birth of a single child. Twins appear in approximately only one of ninety pregnancies, while triplets are extremely rare. It is true that even quintuplets may occur, though up to 1904 only 29 authentic instances could be collected from the whole range of medical literature.

Twins are most frequently born to parents whose ancestors have established this tendency; the trait is usually inherited from the mother's family, though occasionally it is passed on through the father. Of course, that does not explain the cause of twins, which in reality may result from either of two circumstances. More commonly their genesis depends upon the ripening of two eggs at about the same time and the fertilization of both by two different spermatozoa. The children, in this instance known as double ovum twins, may be of the same sex or not. On the other hand, single ovum, or identical, twins are always of the same sex; this follows, since but one egg and but one spermatozoon are here concerned. The incident permitting twins to develop from a solitary ovum must occur soon after conception has taken place. It will be remembered that the first step in the development of the fertilized ovum consists in its dividing into two cells. Ordinarily, both these take part in the development of one embryo, but occasionally they separate and give rise to two. Frequently, the presence of twins can be recognized during the latter months of pregnancy, and accurate means are known of determining after they are born to which variety any given pair belongs.

THE RATE OF GROWTH.—When we recall the definite and often marked differences in the physical character of women, such as weight and height, it is surprising to learn that the prenatal development of their children proceeds with uniform speed. One very practical result is that the physician is thus enabled, at the birth of a premature infant, to estimate accurately the period of its development. Various criteria, some of which are easy of application, aid in this determination. For example, the length of the child is practically constant for each of the ten lunar months into which the whole gestation period is divided; if, therefore, the length of the newborn infant is known, the stage of its development can always be inferred. From the fifth month the calculation is especially simple, since the length measured in centimeters divided by the figure 5 gives the month to which pregnancy has advanced. Similarly, we can infer the period of development from the weight, though the calculation is more intricate and the method less reliable, inasmuch as the size of the child in the latter months varies somewhat according to the weight of its mother.

At the end of the fifth month, the weight of the fetus is from nine to ten ounces; whereas an average infant when born at the expiration of the full term of pregnancy, that is, with the completion of the tenth month, weighs about seven pounds. The fetus, therefore, acquires roundly ninety per cent, of its weight during the second half of pregnancy, which clearly indicates that Nature reserves this period of gestation for the fetus to increase in size, a phenomenon less mysterious but no less important than the evolution of the embryo.

Nothing is more valuable than the weight in affording an indication as to whether a prematurely born infant may be reared. It is unusual to raise a child weighing less than four pounds, which corresponds approximately to the end of the eighth lunar month of development (a trifle more than the seventh calendar month). After this time, the prospect of living becomes greater in proportion to the nearness with which the infant has approached maturity. No truth exists in the widespread belief that the seventh-month child is favored above that born later but before the natural end of pregnancy. Experience has taught that the probability of success in rearing the child increases rapidly after the seventh month. This is reasonable on the following somewhat theoretical grounds. The digestive organs later attain a higher state of perfection, and are better prepared to carry on their work satisfactorily. Moreover, the gradual deposition of fat beneath the skin during the last two months of pregnancy materially assists in fitting the child for the conditions met with in the external world, since the fat affords a barrier against the escape of heat generated within the body, making it much easier to keep the child's temperature at the normal point. Even other more technical reasons could be given to demonstrate the error of the superstition regarding the seventh-month child—a conviction endorsed by medical men hundreds of years ago and as yet not discarded by the laity.

When pregnancy has reached "term," the child, having completed its prenatal development, is ready to cope with conditions as they exist in the external world. At term the average child is twenty inches long and weighs 7 1/7 pounds (3,250 grams). The length is remarkably constant; but the weight, as is well known, is often somewhat above or below the average figure. In a general way, smaller children occur in the first than in subsequent pregnancies, and, moreover, may be expected when the mother is a small woman, or poorly nourished, or has worked hard during her pregnancy. On the other hand, a tendency to bear large children is present when the opposite conditions prevail. It is not unusual to see infants weighing eight or nine pounds at birth, but babies of more than ten pounds are rare, and the fabulous, though not infrequent, reports of fifteen and twenty-pound infants are probably not based upon actual weighings, but upon the impression of someone who has merely seen the child or perhaps guessed the weight from lifting it.

Although the fetus frequently changes its position during the earlier months of pregnancy, generally by the beginning of the tenth lunar month it has assumed a permanent posture. It has then reached such a size that it can best be accommodated in the cavity of the uterus if its various parts are folded together so as to give the fetus an ovoid shape. To secure this form its back is arched forward, and its head bent so that its chin touches its chest; its arms are crossed just below the head, its legs raised in front of the abdomen, and its knees doubled up. In this form the fetus occupies the smallest possible space.

With relation to the mother the position of the child, for several weeks before birth, is one in which its long axis is parallel to the long axis of her body. This remains true no matter whether the head or the buttocks are to precede at the time of birth. In ninety-seven out of a hundred cases, however, the head lies lowermost and consequently is the first portion of the child to be born. The opposite position, in which the head is the last portion born, is, even with the most skillful treatment, somewhat more serious for the infant, though not for the mother.

THE NEWBORN INFANT.—The baby at birth is not a miniature man. As compared with an adult its head and abdomen are relatively large, its chest relatively small; its limbs are short in proportion to the body; and at first glance it appears to have no neck at all. The middle point of a baby's length is situated about the level of the navel, whereas in a man the legs alone represent approximately half his height. The changes after birth consist chiefly in growth; but not altogether, since at least one organ, the thymus gland, becomes smaller and completely disappears during childhood, and other organs, especially the liver, are proportionately smaller in the adult than in the infant.

The body of the infant also differs from that of the man in possessing greater softness and flexibility. These qualities depend upon the nature of its skeleton, which is composed of more bones than later in life, when several have fused together to form one to give the mature body a more rigid frame. Furthermore, the individual bones are not so firm, consisting of an elastic material called cartilage, so that some movements which in an adult would cause such serious injuries as fractures and dislocations are perfectly harmless to a newborn child.

The legs are not only short in proportion to the body but are always curved, and the feet are held with the soles directed toward one another, a position clearly abnormal in the adult. But every mother should know that these are natural conditions in the infant, and are the result of the posture of the child before birth. They soon straighten out. The bowed legs of an adult are of an entirely different origin, resulting from a disturbance of nutrition in infancy called rickets.

A small amount of short wooly hair is usually found over the back of a newborn infant. More conspicuous, however, is the presence there of a gray, fatty substance which, though always more abundant over the back, is at times distributed over the whole body; rarely is it entirely absent. The material, technically named the vernix, is the product of the glands in the skin and is a perfectly normal secretion. After its removal, which is readily accomplished by greasing the infant with lard or vaselin before giving the initial bath, it never reappears.

A varying amount of hair covers the head of the infant. No significance should be attached to the quantity, for the conviction that exists, especially among negroes, that a heavy suit of hair for the child occasions "heart-burn" in the mother during pregnancy is without foundation. The color of the hair at birth does not indicate its ultimate shade; changes are often noted during infancy. Similarly the permanent color of the eyes is not assumed until later; at the time of birth the eyes are generally, if not always, blue in color.

A baby's head is a matter of great concern to the family. Occasionally, the skull is round and well shaped from the moment of birth, but more often it is long and narrow; sometimes the form is even startling to the inexperienced. The peculiar shape of the head results, of course, from its passage through the birth-canal and is not a sign of any disease. In a few weeks, or even less, the strange appearance passes away. It is unwise to attempt to alter the shape of the head by bandaging or massaging since the growth of the brain will spontaneously accomplish what is desired; interference can do no good, and may do serious harm.

Nature facilitates an appropriate molding of the head during birth so as to permit its easy passage through the bony pelvic cavity of the mother, and gains that end in two ways. The bones of the head remain pliable until after the infant is born, and, further, their edges are not welded together as in an adult, but are separated from one another by an appreciable distance. During the act of birth the edges are brought into contact or even overlap, materially reducing the size of the head. Within a few hours after birth the bones again spread apart, and some months elapse before they begin to unite; the union is not completed until some time during the second year of infancy.

Many mothers are anxious to know how far the senses of the infant have developed when it enters the world. This problem has stimulated some scientific investigation, though hardly so much as its interest would justify. Two lines of inquiry have been pursued toward its solution. The objective point of one of these has been to determine how nearly the sense organs of the newborn correspond anatomically to those of an adult; that is how perfectly has their organization been completed. The other has been to learn how the infant reacts when the various senses are stimulated; the interpretation of these reactions is, however, particularly liable to error and sometimes amounts only to guesswork.

The organization of the nerves and muscles in the eye is far from perfect at the time of birth. The muscles act irregularly; indeed, the lack of muscular adjustment is such that movements of the eye likely to alarm the parents are regularly observed in very young infants. Furthermore they cannot focus images which fall upon their eyes. The retina, which receives visual impressions, has reached such development at birth, however, that sensations of light can be perceived. For example, if a lamp is suddenly flashed before the face of a newly born baby it cries. From this and similar evidence, indicating that strong light irritates the delicate structures of the eye, we have learned that a nursery should not be illuminated, during the day or night, so brightly as the rooms adults occupy. Certainly several weeks, and probably several months, pass before an infant can see anything save as blurs of light and darkness. Objects, such as a hand, probably appear as shadows, which are not correctly interpreted until late in infancy.

In regard to color vision we have as yet no reliable information concerning children under two years of age. Infants of less than a year have been known to distinguish certain colored papers. But such discrimination is probably due to a difference in brightness of the colors.

Although the organ of hearing is well developed at birth, the drum of the ear in very young infants cannot transmit sounds, as in the adult. For the latter kind of transmission it is necessary that the pressure on both sides of the drum-membrane should be equal, and this is arranged by the admission of air to the middle ear through a passage from the throat. At the time of birth, on account of the swollen condition of the mucous membrane which lines this passage, it is blocked, and the middle ear is filled with fluid; these conditions interfere with the transmission of sound, and consequently its perception is dulled. But even in the absence of a drum-membrane an adult can hear; the vibrations in such cases are transmitted through the bones of the skull, and this very likely also occurs in newly born infants. In most instances, at least, they react to a disagreeable noise within the first twenty-four hours, and their sensitiveness in this direction explains why the nursery should be kept quiet.

Investigators have not come to uniform conclusions concerning the sense of smell and of taste. In all likelihood, smell is not acute at the time of birth. Taste probably is better perceived, yet some newborn babies are said to suck a two per cent solution of quinin as eagerly as milk, though stronger solutions are distasteful. According to the best available information a young infant can detect the difference between a sweet, bitter, sour, or salty taste only when the tests are made with a solution possessing the quality in question to a marked degree. It is common knowledge that babies cheerfully suck the most tasteless objects, and it is not improbable that at first the reaction depends upon the temperature of the object and the feeling it creates in the mouth.

The moment it is born, a baby perceives pressure if its skin is touched. To this sensation, however, some parts of the body are much more sensitive than others; the tongue and lips are most sensitive of all. Heat and cold are probably perceived more acutely by infants than by adults; to pain, on the other hand, babies are less sensitive. An infant is aware of the movements of its own muscles, and also appreciates a change from one position to another, as experienced nurses know very well, and on that account carefully avoid keeping a baby on one side continuously.

The vast majority of movements performed by young infants are reflex acts, that is, the cerebrum, the part of the brain with which thinking is done, is not concerned with their performance. Of these reflexes the most notable are sucking and swallowing, but sneezing, coughing, choking, and hiccoughing may also be observed; stretching and yawning have been recorded in several instances, even during the first days of infant life. None of these movements, we must remember, are produced consciously; the baby cannot reason and does not recognize anyone, even its mother.

HEREDITY.—The transmission of bodily resemblance and of traits of character from parent to child is a broad and complicated subject, whose fundamental principles biologists are just beginning to grasp. The facts thus far established regarding heredity relate chiefly to plants and to the lower animals. There is no doubt whatever that the meager knowledge we possess of heredity in man will be amplified and will ultimately indicate on the one hand the marriages which are advisable and, on the other hand, those which are not. Indeed, the foundations for a science called Eugenics, which purposes to improve the human race in this way, have already been laid. It is barely a decade, however, since our knowledge of heredity has approached that order and system which entitle it to be ranked as a science; and in this brief period great strides could hardly be expected in its most intricate field, that of human inheritance.

The modern teachings of heredity are of interest to us, nevertheless, since they intimate the time when a child's inheritance is fixed and the means by which hereditary characters are conveyed. To understand these fundamental points we must recall that at the moment of conception a male germinal cell combines with a female cell, and that this act, which is named fertilization, brings together vital elements from the two parents. We have seen that the spermatozoon represents the solitary contribution of the father toward the development of the child, and the spermatozoon, therefore, must convey the material basis of paternal inheritance. Similarly we might expect the ovum to be the bearer of the maternal qualities inherited by the child. This is actually true; but much of the evidence is of a technical character and must be omitted. Yet an experiment successfully conducted by Castle and Phillips will indicate, even to those who have no special knowledge of the mechanism of heredity, the important role the ovum plays. These investigators removed the ovaries from an albino guinea-pig, and in their place substituted the ovaries of a black guinea-pig. "From numerous experiments it may be emphatically stated that normal albinos mated together produce only albinos." But in this experiment the result was otherwise, for the albino into which the ovaries of a black guinea-pig were grafted produced only black offspring. The color-coat of her young, therefore, was not influenced by her own white hair, but was determined by the eggs really belonging to the black animal from which the ovaries were taken; in no other way can the result be interpreted. It is certain, moreover, that the mode of transmission of material qualities here exemplified is not exceptional; on the contrary there is no doubt that the ovum always conveys the sum total of the qualities the offspring inherits from the mother.

The germinal cells then contain the material basis of inheritance, and in all probability the substance is located within the nucleus of the cells. This substance had been seen and studied long before its relation to the problem of heredity was suspected. Because it takes a deeper stain than the rest of the nucleus, it stands out prominently when the cell is treated with certain dyes, and this property accounts for its name—chromatin. Under such conditions as prevail just before a cell divides, the chromatic substance is broken up and reassembled in the form of rods called chromosomes. Curiously enough the number of rods is uniform for each species of animal, though different numbers are characteristic of different species; the characteristic number for man is twenty-four.

Unless some arrangement was made to prevent it, the act of fertilization would cause the number of chromosomes in the fertilized ovum to be double the number characteristic of the species. In man, for example, the addition of twenty-four chromosomes from the spermatozoon to an ovum that already contained twenty-four chromosomes of its own would mean that after fertilization the ovum contained forty-eight. Such a result is prevented through the process to which we have referred in the preceding chapter as the ripening of the ovum, and also through a similar process in the case of the spermatozoon. These two processes lead to a reduction in the number of chromosomes, so that finally every human germinal cell contains twelve, and therefore when the ovum is fertilized the characteristic number twenty-four is restored. While we know nothing of the forces which determine, on the one hand, what elements shall be discarded by the germinal cells and, on the other hand, what elements shall remain, it is definitely proved that a selective process always takes place. This fact admirably explains the variation in the characteristics inherited by children of the same family. So far as is known, the traits which will be passed on from either parent are a matter of chance. Whatever these hereditary traits happen to be, the best evidence we have indicates that the problem of a child's inheritance is settled once for all the moment conception takes place.

MATERNAL IMPRESSIONS.—Contrary to all that we know of heredity, the conviction prevails among the laity that the character of a child depends greatly upon the mother's surroundings during pregnancy: this is the doctrine of maternal impressions. As is usual with superstitions, this one emphasizes the unfavorable possibilities and holds that the unborn child may be affected by the mother's unhappy thoughts or maimed by her mental distress if she is exposed to unpleasant sights. For this belief there is no foundation; the cases often cited in its support may be fully explained on the grounds of coincidence.

With the possible exception of such individuals as are spending their lives in solitary confinement, there is scarcely a human being who has not in the course of nine consecutive months some untoward physical or mental experience which engraves itself upon the memory. Prospective mothers are not apt to be exempt from a rule so general in its application, but if by good chance one happens so to be she will hardly fail to hear of the misfortune of others, which, according to the doctrine of maternal impressions, may be equally effective in interfering with the proper development of the child. We should then rightly expect most, if not all, babies to be "marked"— clearly a situation which does not prevail.

In order to learn how frequently prospective mothers may have disagreeable experiences which they fear will affect the formation of the child, I have lately asked the patients whom I have attended, "Was there any incident during your pregnancy to which you could have attributed the infant's condition, had it been marked?" The babies of all those to whom the question was submitted were normal; yet without exception those whose pregnancies just completed were their first answered in the affirmative. It is also pertinent that one of these patients had lost her brother by a violent and accidental death when she was four months pregnant; a similar bereavement was suffered by another at the eighth month; each was, however, delivered of a perfectly healthy child. Among those with whom the recently ended pregnancy was not the first I found some who could remember incidents popularly believed to have an influence over the development of the embryo; most of them, however, had given the matter so little thought that they could not definitely recall whether such incidents had occurred or not. From a similar series of observations covering two thousand cases, William Hunter came to the conclusion, nearly two hundred years ago, that there was no support for the belief in maternal impressions.

Whenever a child does happen to develop abnormally, it must be clear that, from the very nature of our existence, some incident can be recalled which will satisfactorily, yet unjustly, bear the blame. It may be confidently said, however, that, for every mother whose fears are realized, hundreds are agreeably disappointed in finding their babies perfectly normal. In the face of so many negative instances it is amazing that any person, even though ignorant of medical teaching, should be inclined to attribute abnormal development to something the mother has seen or heard, thought or dreamt, or otherwise experienced while she was pregnant. Yet unfortunately many do believe this. It is worth while, therefore, to supply further evidence, and thus escape any suspicion of unfairness in argument, to prove that maternal impressions are unable to affect the formation of the embryo.

It is found, as a matter of experience, that the superstition regarding maternal impressions generally begins to cause anxiety during the second half of pregnancy; and then such an influence is entirely out of the question. By the end of the second month the form of the embryo has been definitely determined, and subsequently cannot be altered. It is even true that errors in development are most apt to occur within the two or three weeks that immediately follow conception, and therefore occur at a time when pregnancy is not often clearly recognized. Thus it happens that women begin to worry about the influence their minds will have upon the formation of the child long after its form has been established.

Incidents in the life of a prospective mother are in point of fact equally inert so far as their influence upon development is concerned, no matter whether they occur during the earlier or later part of pregnancy. There is never any anatomical means by which maternal impressions could be conveyed to the embryo. Such an influence would have to be exerted through the placenta; and that is impossible. There are no nerves in the placenta to carry impulses from the mother to the child. Even the blood streams of the two beings are kept apart; and though it is unheard of that the blood should carry nerve impulses, if that happened to be the case, it could not prove effective here, for the blood of the mother does not enter the child. It is nourished by food which passes from the mother's blood, to be sure, but there is no more reason to expect this nutriment to exert an hereditary influence than there is to expect an infant to grow to resemble the cow with the milk of which it is fed. With these two possibilities eliminated, no path can be imagined by which impulses might travel from the mother to the embryo.

Scientific investigation has brought to light these facts, as it has also taught the real causation of the disfigurement once attributed to the mother's mind. Departures from the usual form of the body occur during the earliest days of pregnancy and arise in consequence of some irregularity in the process which molds the body-form from a simple spherical mass of cells. Why irregularities sometimes occur is not altogether clear; except in so far as it has been determined that the fault lies within the embryo itself. Whenever these defects are associated with events which have disturbed the mother's mind, it cannot be other than a simple coincidence.



CHAPTER IV

THE FOOD REQUIREMENTS DURING PREGNANCY

The Food-stuffs: Water; Mineral Material; Protein; Carbohydrate; Fat— What We Do to Our Food—How Much Food Is Needed During Pregnancy?— The Importance of Liquid Nourishment—The Choice of Food—Cravings— The Relation Between the Mother's Diet and the Size of the Child.

There is a gain in weight during pregnancy amounting finally to about thirty pounds; exceptionally, it is as little as ten or fifteen pounds, and, at the other extreme, as much as forty or fifty. With individuals inclined to be stout the increase is greater, and it is relatively greater in later pregnancies than in the first. During the early months of pregnancy the weight generally remains stationary or suffers a slight loss; even in those rare instances in which the weight begins to increase shortly after conception the gain is less marked in the earlier months than later. For the last three months the average monthly gain has been found to be between three and a half and five and a half pounds.

The weight gained during pregnancy is not, as can be readily understood, permanently retained. At the time of birth, in consequence of the expulsion of the child, the after-birth, the amniotic fluid, and a varying amount of blood, there is necessarily a loss of from ten to fifteen pounds. Later, as the maternal tissues, whose growth has been stimulated during pregnancy, return to their original condition, a further loss in weight takes place. It is not unusual, however, for women to remain permanently better nourished than before they became pregnant. Under ordinary conditions the food of the prospective mother provides not only for her own wants but also for those of the embryo. Between the two organisms there exists a relation which resembles that existing between a house in course of construction and the contractor who supplies the building material. The mother furnishes what is needed to construct the "living edifice," as Huxley called the growing embryo, but she is not responsible for the lines of the building. The embryo is both architect and mechanic, designing the structure and arranging the "organic bricks" in their proper places. The work of construction necessitates the expenditure of an appreciable amount of energy and the creation of waste products that must be removed, lest they accumulate and interfere with the growing structure. These waste products leave the embryo by way of the umbilical cord and the placenta and return thus into the mother's circulation; ultimately they leave the mother through the same channels that carry off her own waste. First and last, then, the nutrition of the mother and of the child are so bound together that it has been impossible to study them separately. Our knowledge of food requirements during pregnancy has been obtained by measuring the food requirements of the mother alone; and as nutrition during gestation is fundamentally the same as nutrition at other times, it is necessary for us first to consider in general the food needed by the human body.

THE FOOD-STUFFS.—The waste products we throw off indicate that the substances which compose our bodies are being constantly broken down and reduced to a condition such that they are useless to us. In normal persons hunger signifies that they need material to replace what has been used up. The substances thus required, if the wants of the body are to be satisfied correctly, are called the food-stuffs; and they are the same during pregnancy as at other times. The foodstuffs are usually classified according to their chemical properties; on this basis they are placed in five groups: (1) Water, (2) Mineral Materials, (3) Proteins, (4) Carbohydrates, (5) Fats.

In view of the different purposes which the foodstuffs serve, it is convenient to group them in another way. Thus, the carbohydrates and the fats may be placed together because they are the body fuel; their value consists in the heat and energy which they yield when acted upon in the tissues. Water and mineral matter, on the other hand, are never a source of energy; they assist in building new tissue or in repairing tissue that already exists. The proteins are unique, in that they may serve either purpose. Primarily the proteins are tissue-builders, but in the absence of sufficient fat or carbohydrate the body burns protein to secure heat and energy.

Each food-stuff, therefore, serves a distinct purpose, and some of them render services which the others cannot perform. A man will die if either water or mineral matter or protein is completely withdrawn from his diet. Fat or carbohydrate, on the other hand, or even both of them, may be excluded for some time without causing serious inconvenience. It is true, nevertheless, that each food-stuff performs some task better than any of the others can perform it, and for that reason all of them should be included in the diet of an healthy individual.

Some of the food-stuffs, such as water and table salt, come to the body separate from the others; but generally the different types reach us intimately mingled in the various articles of food in common use. Foods vary greatly, however, in the amount of the different food-stuffs they contain. The meats, for example, have a relatively large protein content; in the vegetables starch, which is one of the carbohydrates, predominates. As to the choice of food and the amount that is necessary for the average person, generally the appetite is a safe guide; but the accurate observations of physiologists have gone so far as to determine the exact requirements of the body. Not the least important principle taught by these investigations is to avoid dietary fads, for in arranging a satisfactory diet the problem to be solved is not, What is it possible to live on? but, What serves best as nourishment? The experience of countless generations has taught us that we thrive best on a diet which includes all five food-stuffs.

Water constitutes nearly two-thirds of the weight of the body. As water is constantly being given up in the life process, health demands an abundant supply of liquids to replace the waste. The average daily loss has been found to be between two and three quarts. Of this amount the urine constitutes nearly two-thirds; and the remaining third is eliminated through the skin, the lungs, and the bowels. Although the deficiency thus created is met in part by the water in our solid food, the greater part of the loss is made up by the liquids we drink, and we are warned, in a measure, by the sensation of thirst that they are needed.

Mineral material is of the greatest importance as a constituent of our food. It contributes to the welfare of the body in at least three ways; (1) it gives rigidity to the bones, (2) it supplies an essential ingredient of the living substance in all the tissues, (3) it is present in the blood and in the other body fluids, where it is of service in such vital processes as the beating of the heart, the transportation of oxygen to every portion of the body, and the maintenance of an acid or alkaline condition of the digestive juices according as the one or the other is necessary for the assimilation of the food.

An animal deprived of mineral food will die as surely as one deprived of water. In arranging our diets, however, we are not compelled to take the minerals into account, for, with the exception of table salt (sodium chlorid), the meat and vegetables that we eat provide the mineral material the body requires. Iron, for example, which imparts to the blood one of its most essential qualities, occurs in relatively large amounts in apples, spinach, lettuce, potatoes, peas, carrots, and meats. Only now and then does it become advisable to add iron deliberately to the diet. Similarly lime (calcium) the material that makes the bones hard, is present in quantities ample for the needs of the body in the bread, milk, eggs and vegetables that we eat. The remaining mineral constituents of the body, among which the most conspicuous are magnesium, potassium, sulphur, and phosphorus, occur in foods which we are naturally inclined to take, so that we secure an abundance of them unconsciously.

Protein, the third food-stuff which we must eat to keep alive, contains the chemical element nitrogen in such form that it can be incorporated in our tissues. Although most persons derive their protein in part from meat, milk, and eggs, it is possible to satisfy the requirements of the body on a purely vegetarian diet. Experience has shown, however, that it is both natural and advantageous that we employ a mixed diet.

The property of protein to build living tissue and replace tissue waste probably depends upon several factors; but certainly one of them is the presence of nitrogen. So intimately associated are the consumption of the tissue substance and the elimination of nitrogen that we have no better way of judging the amount of tissue substance used in the body than by determining the quantity of nitrogen that appears in its various waste products. From such investigations it has been found that the quantity of protein required to repair the breaking down of the tissues is not great. The average man consumes approximately a quarter of a pound (100 to 120 grams) of protein daily; but this quantity is in excess of his real needs. Indeed, Chittenden has shown that for various classes of individuals, namely, students, athletes and soldiers, half as much is sufficient. Other physiologists, though admitting that this is true, contend that it is inadvisable to regulate one's diet on such a slender basis. Very good reasons are assigned for the view that more protein is needed than just enough to counterbalance the tissue waste. Thus, in the case of animals, it has been found that a diet low in protein finally causes digestive disturbances and other ailments.

Although it does not seem advisable to practise rigid economy in arranging the protein content of the diet, it is equally important that we should not go to the other extreme. The consumption of over- large quantities of protein, as would be the case if we lived exclusively upon meat, increases putrefaction in the intestines and throws unnecessary work upon the kidneys, which are the organs chiefly concerned in getting rid of the waste products of protein.

Carbohydrate is the name given the group of foodstuffs to which the sugars belong. The food value of cane sugar, the most familiar member of the group, was recognized even in prehistoric days by the natives of India. By boiling the plant we call sugar-cane they obtained a substance to which they gave the name Sakkara, and from this our word sugar evidently originated. The roots of this plant were carried into Europe and cultivated during the Middle Ages. Obviously, its value was and is appreciated, since the cultivation of the sugar-cane and the sugar-beet has become the foundation of a great modern industry.

There are some persons, perhaps, who do not realize that beside cane sugar many kinds of carbohydrate occur in our food. Glucose or grape sugar, for example, occurs not only in the fruit indicated by its name, but also in other fruits, in corn, in onions, and in the common vegetables. Glucose is especially suited to act as nourishing food. In keeping with that fact our digestive juices convert most of the sugars we eat, if not all of them, into glucose, which is regularly present in our blood. It is unnecessary to enumerate all or even the more important compounds included in the carbohydrate group; but everyone should know that starch is its chief member, and that after being thoroughly digested starch enters the body as glucose and therefore serves the same purpose as sugar.

The value of carbohydrates as a source of heat and energy may be accurately measured, and is technically expressed in terms of a unit, called the calorie. As the energy which our bodies require may be estimated in the same terms, it is possible to determine whether or not our food is equal to our wants. Very naturally the energy requirements of any individual are influenced by his weight and by the work he does. But we may take as a standard the results of an extensive study of American families which indicate that women require four-fifths as much energy-yielding food as men. It also seems safe to conclude that a woman weighing 130 pounds who does her own housework requires food every day having an energy-value of 2,500 calories; smaller women and those who do no work require somewhat less. In a mixed diet the chief source of this energy—and the source from which it is most economically obtained—is the carbohydrates.

Fat yields more energy and heat than does carbohydrate, bulk for bulk; but fat is burned by our tissues less readily. We instinctively avoid eating a great deal of this food-stuff; in the course of a day the average person consumes no more than one or two ounces. The natural aversion which many feel toward fat may possibly depend upon the difficulty with which they assimilate it. In colder climates, however, we know fat to be a staple article of diet; and it is not unlikely that the very conditions which make it necessary there explain the unusual tolerance for it.

Fat is more than fuel. Deposited in our bodies, beneath the skin for example, it prevents the escape of heat that we generate and protects us against the penetration of cold. This food-stuff, therefore, contributes in several ways toward maintaining the temperature of the body at a constant level.

Our source of fat is chiefly animal food and in a smaller measure vegetables; but the fat our food contains is not altogether responsible for the fat in our bodies. Carbohydrates, if in excess of momentary needs, are partly converted into fat and stored as such. A reserve supply of nourishment is thus provided, and is drawn upon only when the food that we consume does not contain as much energy as we expend.

WHAT WE DO TO OUR FOOD.—With the exception of water and mineral substances, the food-stuffs must undergo chemical alterations before they are capable of being absorbed into the body; this is the work of digestion. The digestive processes, the main purpose of which is to break up the carbohydrates, proteins, and fats into substances of much simpler chemical structure, begin in the mouth and are not completed until some time after the food has entered the intestine. As the food moves through the alimentary canal, it is mixed with the various digestive juices containing ferments, such as pepsin, which are the active agents of digestion. Although digestive processes go on automatically, they are, in a degree that is far from negligible, influenced by the mind. Thus, cheerfulness promotes digestion, and not infrequently mental depression may be the direct cause of indigestion. Indeed, it is chiefly in regard to the state of the mind of the prospective mother that the existence of pregnancy may be said to have a bearing, whether favorable or unfavorable, upon her digestion.

The digestive juices are prepared in glands which lie either within the lining of the alimentary canal or adjacent to it. In the latter event the glands are connected with the canal by means of tubes. These glands must be warned when to pour out their secretion, and their very first warning usually comes from the agreeable sensations experienced when we see, smell, or taste inviting food. If we are hungry, our viands attractive, and our surroundings congenial, the stimulus excites a plentiful secretion of the digestive juices; conversely, the opposite conditions, to some extent, check their flow.

The sight of attractive food, as we all know, "makes the mouth water," that is, it calls forth the saliva which contains one of the digestive ferments. Thus, at the beginning of a meal, favorable conditions for digestion are established. The saliva, however, acts only upon starch; and, moreover, its action upon this carbohydrate is weak unless the food is thoroughly chewed and mixed in the mouth. Most of us, perhaps, overlook the importance of mastication, which not only crushes all the food-stuffs, preparing them for efficient digestion, but also stimulates the flow of the digestive juices. Furthermore, by thoroughly masticating our food, we know intuitively when we have had enough, and thus avoid overeating.

In the stomach the digestion of starch is continued for a time, but the chief work of gastric digestion concerns the proteins. They alone are attacked by pepsin, a ferment secreted by the mucous membrane of the stomach. Moreover, since pepsin is able to act only when an acid is present, the gastric mucous membrane also secretes hydrochloric acid.

Just as the digestive glands in the neighborhood of the mouth become more active when we are conscious that desirable food is at hand, so do the glands in the stomach. Mastication also stimulates the flow of the gastric juice, and this flow is greater if we enjoy what we eat. Furthermore, it has been shown that, after entrance into the stomach, the food itself increases the flow of the digestive juices. All articles of food are not, however, equally efficient in producing this effect: thus meat requires more pepsin for satisfactory digestion than bread, and consequently meat calls forth a larger quantity of gastric juice.

Fat in all probability is not digested in the stomach; even starch and protein are not broken down sufficiently by the time gastric digestion is complete to permit them to be absorbed into the body. "The value of digestion in the stomach," as Howell says, "is not so much in its own action as in its combined action with that which takes place in the intestine." It is even possible for satisfactory digestion to take place without the assistance of the stomach. This fact has been substantiated by several cases in which men have lived for years after the stomach was removed to eradicate a disease. It is true, nevertheless, that intestinal digestion can be performed more economically if it begins where gastric digestion normally leaves off.

Of the changes wrought in the food by the various digestive processes, those which are the most profound take place in the intestine. While the food is being moved through this organ—some thirty feet in length—it is reduced to simple chemical fragments, which are absorbed by the intestinal wall. Digestion in the intestine is carried on through the agency of a number of ferments, the more important of which are supplied in the juice manufactured by the pancreas. The pancreatic secretion contains three separate and distinct ferments, which act respectively upon carbohydrate, protein, and fat. The absorption of fat, however, is materially assisted also by the action of the bile.

A part of what we eat always escapes digestion; the unused portion, it has been estimated, is somewhat less than one-tenth of an ordinary mixed diet. The residue from vegetables is notably larger than the residue from meat. The undigested portions of all the food- stuffs collect in the lowermost portion of the intestine and form a part of the feces. Here also are gathered the indigestible material we have eaten, the products of bacterial decomposition in the intestine, and other waste substances that the body should throw off.

HOW MUCH FOOD IS NEEDED DURING PREGNANCY?—In connection with the development of the child we have already referred to the difference in the purpose of the constructive processes which go on in the earlier months of gestation and those which take place in the later months. In a general way the first half of pregnancy is occupied with the formation of the embryo from relatively simple structural elements, the second half with its growth into an infant, which acquires ninety per cent. of its substance and weight at birth after the fifth month of embryonic development. A similar contrast may be observed in the nutritional processes of the mother. Often, at the beginning of pregnancy, the appetite is poor and there is indisposition of one kind or another, with the natural result that there is slight if any change in the mother's weight; whereas later a period ensues when her appetite increases, her health improves, and she gains in weight.

Since it is natural that the weight of the mother should remain practically stationary during the early months of pregnancy, it is clear that a diet which has previously been ample will likewise be sufficient for some time after conception has taken place. To most persons, however, it is not clear that the quantity of food ordinarily eaten will suffice also during the later months of pregnancy. On the contrary, popular opinion holds that the prospective mother "should eat for two." It is not unimportant to point out the erroneous character of this superstition, because overeating during pregnancy is much more likely to provoke discomfort than insufficient nourishment.

In order to comprehend the nutritional needs of the prospective mother, one must keep in mind the fact that our food always serves two purposes. These are, as we have seen, to build or to repair tissue and to furnish heat and energy. Since these needs of the body during pregnancy—as at all other times—are best understood when considered in their relation to the food-stuffs which supply them, we shall take up these various ingredients separately.

Protein, which repairs tissue and also furnishes the substance from which new tissue is made, is used more economically during pregnancy than when the maternal functions are inactive. As a result of this economy the same allowance of protein which is sufficient before conception is sufficient also during pregnancy. This fact has been put in the clearest light by extensive observations made upon animals. Dogs which were not pregnant, for example, have been carefully fed so that their food should contain just enough protein to cover the needs of the body and keep their weight constant. Subsequently, when these animals became pregnant precisely the same amount of protein was fed to them. The result was that they gained in weight, and at the same time the waste products of protein they threw off were notably diminished. Such observations, of which there have been a large number yielding concordant results, may be safely taken to mean that an amount of protein previously satisfactory for the animal is also sufficient for her during pregnancy. We are forced to conclude that protein was used more sparingly in the latter condition—a view which has been repeatedly confirmed with regard to human beings as well as animals. It is found, for example, that an amount of protein competent to meet the needs of a man of a given weight will not only provide for the wants of a woman of equal weight while she is pregnant, but will also leave a surplus sufficient for the growth of the fetus.

With regard to the mineral substances, likewise investigations indicate that the "housekeeping" of the body during pregnancy proceeds along unusually economic lines. It is not advisable, therefore, to make any change in the diet with regard to these substances. Attempts have been made to cut down the amount of minerals in the food for the purpose of softening the fetal skeleton. The success sometimes attributed to these efforts is, however, very doubtful, for we know that the mother's tissues will be robbed of minerals for the embryo whenever her food fails to contain them in sufficient amount for her own needs and those of the child. Practically speaking, the mineral content of diet during pregnancy requires no thought, for so long as meat and vegetables are eaten in satisfactory quantity the mineral nutrition will take care of itself.

The food-stuffs which supply heat and energy, since the amount of energy utilized by the body during the latter months of pregnancy is somewhat in excess of that previously required, do not follow the same rule as the protein and the mineral matter. It has been found that just before the fetus becomes mature the energy requirements of the mother are approximately one-fifth greater than in the non- pregnant condition. It is certain, however, that no extra demand for energy exists until the fifth or sixth month of pregnancy, and that the excessive requirement is extremely small until the last three or four weeks. Even then the prospective mother requires less energy- giving food than the average man.

Since the body handles carbohydrate more readily than fat, it is preferable that whatever additional energy pregnancy necessitates should be supplied by carbohydrates. An increase in the daily consumption of fatty food, over and above that previously found agreeable, is not only unnecessary but undesirable. Every-day experience teaches that less fat taken with the meals promotes the comfort of the prospective mother. A glass of rich milk a little before meal time, however, not only makes up for this omission but also prevents "heart-burn," a very common ailment of pregnancy.

Although there is an appreciable increase in the quantity of starch and sugar utilized toward the end of pregnancy, it is generally quite unnecessary to increase these materials correspondingly in the diet. Nearly everyone eats more of all the food-stuffs than the body needs. In the case of the prospective mother the surplus ordinarily taken meets every need incident to her additional energy requirements. Because we eat more than we need, someone has said, with as much truth as humor, that prospective mothers "neither want nor need to eat for two. The fact is more likely that enough for one is too much for two." For the average woman it is wiser to take less during pregnancy rather than more, for over-indulgence is apt to lead to indigestion. The moment when the appetite is satisfied should be accepted as the stopping point, and that will be instinctively recognized if one eats deliberately, and thoroughly masticates the food.

Regularity in the hour of eating is always healthful, and for some prospective mothers three meals a day prove quite satisfactory. Not a few, however, who adhere to this habit make the mistake of eating more than is wise; and large meals are particularly inappropriate to pregnancy. On this account most prospective mothers will be more comfortable if they take some simple and wholesome nourishment at fixed times between meals. Such an arrangement modifies a ravenous appetite, and it is, at the same time, beneficial to those who are not inclined to eat enough at the regular meals. If small amounts of food are taken five or six times a day, a tendency to be nauseated, which is not uncommon in the early months of pregnancy, can often be averted. In the latter months, too, because the capacity of the stomach is diminished through the encroachment of the enlarged womb, frequent meals generally contribute toward comfort and health. While the inevitable consequences of overloading the stomach are to be avoided at all times of the day, it is especially important to remember the disagreeable results of a hearty meal at night. The evening meal should be a light one and should be eaten three or four hours before going to bed.

THE IMPORTANCE OF LIQUID NOURISHMENT.—Every prospective mother should have brought to her attention the great importance of drinking water at regular times and in larger quantities than was formerly her custom. Since water constitutes two-thirds of the substance of our bodies, it is necessary, of course, for everyone; but during pregnancy it is especially necessary for the building of new tissue and for safeguarding the mother's kidneys. Prospective mothers would protect themselves against a number of ailments if they were more careful to drink a sufficient amount of liquids. They may easily determine whether they are doing so, for whenever the urine passed during twenty-four hours measures less than a quart, they are not drinking enough. Generally the daily elimination of urine fluctuates between two and three pints; a larger amount, however, is rather a favorable indication than the reverse.

The variations in the quantity of liquids that healthy persons drink make it impossible to say just how much anyone should take. It may be said with confidence, however, that women who are pregnant should consume at least three quarts of fluid every day, and by far the greater portion of this should be water. The rest may be taken in the form of milk, soup, cocoa, and chocolate. Against the moderate use of tea and coffee no valid objection can be raised; the tradition that they may cause miscarriage is incorrect. For well-known reasons the habitual use of strong tea or coffee is always harmful, and it is, therefore, equally as objectionable during pregnancy as at other times. Beverages which contain a small percentage of alcohol, such as malt and beer, may or may not be helpful; they should be regarded as medicine, not to be taken without consulting a physician.

THE CHOICE OF FOOD.—There is no diet specifically adapted to the state of pregnancy; the prospective mother may usually exercise the same freedom as anyone else in the selection of food. She should, however, choose what will agree with her and avoid that which she cannot digest and assimilate. Personal experience in the main must guide everyone as to what to eat, and most women may follow the dictates of appetite after they become pregnant as safely as they did before.

It is true, of course, that careful scientific observations have taught not only what the nutritional requirements of the body are, but also how the diet may be arranged to satisfy these requirements most conscientiously and economically. "Caloric Feeding" is the name given the method which aims to furnish an individual the exact amount of food, and usually to furnish it at a minimum cost. Its principles are of great practical importance to the commissary of an army or to the purveyor of an institution which provides for large numbers of people; but it is neither necessary nor advisable that the diet of any healthy individual be regulated solely with a view to satisfying the actual requirements of his or her body. Food should possess other qualities than fuel value: first of all it must be appetizing, for appetizing food receives the most thorough digestion.

We all know how variable are our appetites. What appeals to one will not appeal to another, and frequently the same person has no appetite to-day for food that she will eat with relish to-morrow. Precise rules, therefore, to guide healthy persons in the selection of their food are not obtainable; neither are they desirable, for the exercise of individual preference possesses notable advantages. In order, however, that there may not also be disadvantages, the prospective mother, like anyone else, must be content to choose food that is simple, wholesome, and of such a character that it will not throw an undue burden upon the digestive organs.

During pregnancy some uncooked food should be eaten every day. Ripe fruit answers the purpose admirably. At all seasons of the year fruit of one variety or another, such as apples, peaches, apricots, pears, oranges, figs, cherries, pineapples, grapes, plums, strawberries, raspberries, and blackberries may be obtained and should have a place in the diet. In making a choice personal taste alone need be consulted.

Fruit contains a large proportion of water as compared with other articles of diet; and, therefore, is especially capable of quenching thirst. Fruit also lessens the desire for sweets, acts as a laxative, and furnishes mineral material which the body needs. Its laxative effect is most pronounced when it is eaten alone, as, for example, in the morning before breakfast or at night upon going to bed; cooked fruit taken with the meals acts much less effectively. Fruit and vegetable salads are wholesome, but cannot be recommended indiscriminately during pregnancy, for not infrequently the dressing used with them causes discomfort. Under these circumstances it is obvious that one should do without salads.

The cereals wheat, corn, rye, oats, and barley are the most prominent source of starch in an ordinary diet. Breakfast foods manufactured from grain are not only nutritious in themselves, but their value is increased by the milk or cream used with them. Bread is the staple starch-containing food in this country, and starch is our main source of energy, but it is necessary to eat only a small quantity of bread, if the diet includes a relatively large amount of vegetables. It is advantageous to use bread made from unbolted flour (Graham bread) or from corn meal, because the coarse undigested residue which they leave stimulates the movements of the intestine and assists in overcoming the constipation which is generally associated with pregnancy. Pastry must be avoided by those who suffer from indigestion; and every prospective mother should eat pastry only occasionally, and not very much of it at any time. The best desserts are raw and freshly cooked fruit, preserves, gelatin, custard, ice cream, and light puddings, such as rice and tapioca.

Vegetables should be abundant in the diet of every prospective mother. Some of them, however, are digested with difficulty, and on this account cabbage, cauliflower, corn, egg-plant, cucumbers, and radishes should be eaten sparingly. Occasionally it will be necessary to exclude them from the diet altogether. Other vegetables produce flatulence, and for that reason parsnips and beans may cause discomfort. The prejudice, however, which exists against onions, asparagus, and celery should not be heeded; all of them are harmless, and celery thoroughly cooked with milk is very wholesome. Besides these, moreover, there are many highly nutritious and easily digestible vegetables which can be freely recommended, such as both sweet and white potatoes, rice, peas, lima beans, tomatoes, beets, carrots, string beans, spinach, Brussels sprouts, and lettuce.

Vegetable food contains all the material necessary to sustain life, and some persons prefer to adhere strictly to a vegetarian diet. Most prospective mothers, however, find a mixed diet more agreeable, and this is sufficient reason for using it. Furthermore, no fair objection can be raised against the use of animal food, provided the pregnancy is normal. It is important, nevertheless, to remember that meat contains protein in concentrated amounts, and that meat once a day answers every need not only of the mother but also of the growing fetus.

The ideal animal foods are milk and eggs; they contain every ingredient necessary to repair old and to form new tissues. But usually the prospective mother may have any animal food she wishes: beef, veal, lamb, poultry, game, fish, oysters, and clams. The relatively large fat-content of pork, goose, and duck renders them indigestible for some persons, who, of course, should not eat them.

From what we have learned about foods in general and their relation to pregnancy it is clear that the question so often asked by prospective mothers, "Are there any special directions regarding my diet?" may be briefly answered as follows: Under no circumstances is the need of food increased in the first half of pregnancy. During the last two or three months, while the most notable growth of the fetus is in progress, there is a perceptible increase in the amount of energy expended by the mother, and this may be readily supplied by a glass of milk or some equally simple nourishment between meals. Furthermore, throughout pregnancy, most women are made most comfortable by frequent small meals; they will almost certainly suffer discomfort if heavy meals are eaten three times a day.

The most nearly ideal diet consists of very little meat and a comparatively rich allowance of vegetables and fruit. The food should be chosen with regard to individual appetite and should be varied frequently. Thorough mastication always increases the efficiency of a diet. Thus the food will be most perfectly mixed with saliva and broken into fragments which can be readily attacked by the digestive juices of the stomach and the intestines.

CRAVINGS.—There is a well-known tradition that women who are pregnant are subject to longings for one article of diet or another, and that unless the desire be promptly gratified the child will be "marked." In the light of what has already been said regarding maternal impressions, this evidently is nonsense. A prospective mother, like anyone else, does frequently desire one article of food more than another. So long as the object of her wish is not obviously harmful, it should be granted; but if it is not granted no harm will come to the child.

Remarkable instances in which disgusting substances have been craved and eaten are often talked about and have even found their way into popular novels. The unfortunate victims of these unnatural cravings are not of sound mind. With reference to them a physician of unusually broad experience wrote fifty years ago, "I have never met with any example of this sort; which leads me to infer that these longings are more frequent in books than in the practice of our art." This conclusion is even more fully justified to-day than when originally expressed.

THE RELATION BETWEEN THE MOTHER'S DIET AND THE SIZE OF THE CHILD.— With the beginning of careful, scientific study of the nutritional problems of pregnancy, investigators were interested to learn the source of the material which was used to build up the child's body. Two possibilities suggested themselves: one that the material came from the mother's food and the other that it was derived from her own flesh. In order to determine which of these methods was the natural one, animal experimentation was resorted to and gave identical results in the hands of independent observers. It was found, as I have already stated, that the same diet which had previously kept an animal's weight constant was sufficient to meet her requirements during pregnancy and also to provide for the growth of her offspring. The mother animal was actually found somewhat heavier at the termination of pregnancy than at the beginning. It seemed fair to conclude, therefore, that nutrition had proceeded along more economic lines, and that under these conditions the customary diet had furnished the material for the formation of the young. Still other observations indicated that, if the food is not sufficient for both mother and offspring, it is Nature's plan to protect the young and leave the mother's wants incompletely satisfied. On the other hand, when an unnecessarily large amount of nourishment is taken, the excess is stored partly in the young, and partly in the mother's body.

There can be no doubt that the results of such observations upon animals are applicable to human beings. Everyone familiar with the practice of obstetrics knows that women who gratify enormous appetites during pregnancy, especially if they also fail to take exercise, give birth to large children. On the other hand, it is said that children born during times of famine are frequently delivered prematurely, or, if mature, they are small and puny. A similar though much less marked contrast exists between the babies of the working classes and the well-to-do, and clearly indicates that the weight of the baby varies directly with the food of the mother.

The quantity of the food is more influential than its quality, though the latter is also a factor in determining the size of the child. An excessive amount of starch or sugar in the mother's diet is stored as fat in the child. On this account it is reasonable to eat sparingly of candy, cake, and other sweets; but further attempts to reduce the weight of the fetus by discrimination against different articles of food are not advisable.

The various theories that have been advanced with a view to reducing the size of the child are impracticable; some of them, rigidly carried out, would actually jeopardize the health of both beings. All of them are designed to make the infant's bones soft and to diminish the fat in its body. To this end, generally about two months before the expected date of birth, the mother's diet is arranged to consist chiefly of meat; and as far as possible she is denied candy, sweet desserts, soup, bread, cereals, vegetables, and water. Such a diet overlooks, among other things, the tremendous importance of liquids to the woman who is pregnant. Certainly its indiscriminate use would result in far more harm than good; and no one should adopt it without minute directions from a physician.

Attempts to make the infant's bones soft by limiting the mother to food containing extremely small amounts of lime and other minerals are also unnatural, for we have learned that whenever the mother's food fails to contain the material the fetus requires the mother's tissues are called upon to supply it. Under these conditions, therefore, her bones will give up their lime.

It is of the very first importance that the mother's nourishment be correct from the standpoint of her own requirements, and such treatment will also redound most beneficially to the child. She should never fall, however, into the error of over-eating, which will not benefit her and will cause unnecessary growth of the fetus. On the other hand, there can be no justification for measures that tend to weaken her. She may be careful, in other words, to avoid over- growth of the fetus, but should not adopt a diet so restricted as to interfere with normal development. So long as her health is successfully maintained, she may give herself no concern as to what the size of the child is likely to be. That is a detail which concerns her physician, and which will be observed by him several weeks before the expected date of birth.



CHAPTER V

THE CARE OF THE BODY

The Bowels—The Kidneys—The Skin—Bathing—Douches—Clothing— Corsets—The Breasts.

If we stop to think it is only too apparent that the human body is a machine. We seize energy in one form and convert it into another, just as truly as do the windmill, the locomotive, and the dynamo. In the case of the human machine, the latent energy of the food is turned into the various activities of everyday life. Our bodies utilize their fuel more perfectly than any machine that man has invented; but they fail, nevertheless, to do so completely. And just as the efficiency of an engine cannot be maintained unless the smoke escapes and the ashes are raked away, so no human being can enjoy health unless his waste products are promptly removed. The task of removal, as most of us know, is assumed by our excretory organs, which include the bowels, the kidneys, the skin, and the lungs.

During pregnancy the mother must get rid not only of her own waste products, but also of those of the child. The waste products of the child, if weighed, would not amount to a great deal; but they are by no means negligible. So far as we can tell, it is chiefly on account of their peculiar character that they increase the work of the mother's excretory organs. Whatever the cause, they do increase it, and experience has taught us that these organs must always be kept in a healthful condition to protect both the mother and the child from harm. Consequently a prospective mother who wishes to take proper care of her body must, in the first place, direct her attention toward keeping up the normal activity of all the excretory functions.

THE BOWELS.—While pregnant, nine out of ten women suffer from mild constipation. Those who have been previously troubled with this complaint may find it aggravated from the outset, but in most instances it does not appear until after several months have passed. Constipation is explained by the fact that the enlarged womb presses against the intestines; and, as the enlargement increases, constipation generally becomes more pronounced. No doubt there was a time when women, perhaps unconsciously, counteracted this natural result of pregnancy by the use of a diet consisting largely of fruit and vegetables and also by outdoor exercise. Such measures, indeed, still afford the simplest means of overcoming constipation.

Throughout pregnancy the bowels should move at least once every day. When they do not, some of the waste material that should be removed is absorbed by the body and seeks to leave it through the organs that are already doing their full share of work. For example, under such conditions, the kidneys, instead of exerting themselves more vigorously, may become less active than they were.

It is everyone's duty to form the habit of having the bowels move regularly. Now the most favorable opportunity for assisting the intestines to empty themselves occurs shortly after meal-time, since the involuntary movements of the intestines are most active while digestion is in progress. It should be regarded as an imperative duty, therefore, to grant Nature such an opportunity every morning just after breakfast. This should be done at a definite hour, day after day, even though the inclination is absent; and in many instances the desired habit will be formed.

A glass of water on going to bed or on getting up has a laxative effect; and there are other dietary measures which may be employed with advantage. Thus, coarseness of the food, as we know, stimulates intestinal activity, and this fact explains the peculiar value of Graham bread, bran bread, and corn bread. Fresh fruit and vegetables counteract constipation for two reasons, namely, because they leave in the bowels a relatively large amount of undigested substance, and because they contain ingredients that have a specific purgative action. Such ingredients are especially noteworthy in rhubarb, tomatoes, apples, peaches, pears, figs, prunes, and berries.

Enemas used as a routine measure are mischievous. They interfere with the "tone" of the bowel-muscle so that it acts sluggishly and bring about a condition in which the bowels will not move without artificial stimulation. At best these irrigations remove no more than the contents of the lower bowel, and should be employed only when there is acute and urgent need of clearing out the rectum.

Obstinate constipation is uncommon, and strong purgatives are seldom needed. If they become necessary, a physician should be consulted as to what to take. Whenever dietary measures and exercise, which is discussed in the next chapter, fail to counteract the natural tendency toward constipation, the prospective mother may generally resort to "senna prunes" or some equally simple and harmless household remedy. Senna prunes are prepared as follows: Place an ounce of dried senna leaves in a jar and pour a quart of boiling water on them. Allow to stand two or three hours; strain off the leaves and throw them away. To the liquor add a pound of prunes. Cover and place on the back of the stove, allowing to simmer until half the liquor has boiled away. Add a pint of water and sweeten to taste, preferably with brown sugar. The prunes should be eaten with the evening meal. The number required must be learned from experience. Begin with half a dozen, and increase or decrease the number, as required. The syrup is an even stronger laxative than the prunes.

THE KIDNEYS.—Any one may judge for herself whether or not the bowels are doing their work satisfactorily, but not so with the kidneys. For this purpose the urine must be examined by a physician. In spite of this fact, considerable responsibility rests upon the prospective mother, whose duty it is to collect the specimens properly—a detail that is apt to be neglected. It is impossible to urge too strongly the importance of saving, at regular intervals, all the urine passed in twenty-four hours, of protecting it from decomposition, and of sending a sample to the physician. The intervals may be longer at first, for the kidneys have very little extra work to do until the sixth month. Usually, therefore, it is a satisfactory plan to send a sample for analysis the first of each month during the early half of pregnancy; but during the latter half one should be sent the first and the fifteenth of each month.

To estimate the exact amount of urine passed in twenty-four hours and to protect it properly, in the first place, the vessel in which it will be collected should be carefully scalded out. As a further precaution against decomposition, add a teaspoonful of chloroform to the vessel, which should be kept covered, and not allowed to stand in a warm room. Unless these details are conscientiously observed, putrefaction may take place and vitiate the analysis the physician wishes to make. The precise amount of urine which the kidneys excrete in twenty-four hours will be determined as follows: At a convenient time, for example at 8 A.M., empty the bladder and throw the urine away; this marks the beginning of the observation. Subsequently, save all the urine passed during the day and night, and finally at 8 o'clock the next morning empty the bladder and add this urine to that previously collected. The total amount, thus collected, should be measured.

It is unnecessary to send all the urine to the physician; six ounces, somewhat less than half a pint, will be enough. But the physician should know what the total amount was found to be; therefore, a record of the measurement, the date, and the patient's name should accompany the sample. If limited to a single fact about the urine, it would be most helpful to know the amount passed during the twenty- four hours. In this way, as I have already pointed out, the patient herself may derive valuable information, for if the urine is scanty in amount—that is, less than a quart—she should drink more water.

Unscrupulous newspaper advertisements alarm people through incorrect statements about trouble with the kidneys. For example, they declare that a sediment in the urine is a sign of disease; but that is false. The mere act of cooling sometimes causes substances to crystallize out of perfectly normal urine. Or, putrefactive changes which frequently take place after the urine has stood for a time may cause some of its normal constituents to be precipitated. A sediment, either white, pink, or yellow, may indicate that the urine is too concentrated, and consequently means that the individual should drink water more freely; but it generally means nothing more serious. The really important abnormal constituents of the urine, namely, albumin and sugar, never form a sediment.

"Pain in the back" is a complaint frequently used to defraud the public. This symptom does not indicate Bright's disease. It is generally due to the muscles far away from the kidneys, with which, usually, the pain has nothing whatever to do. Similarly a desire to pass the urine frequently does not indicate any disturbance of kidney function, but is explained by the pressure of the enlarged womb against the bladder; it is a very annoying, yet a natural, result of pregnancy.

THE SKIN.—The functions of the skin are at the very foundation of health. It protects the delicate structures which it covers, assists in the regulation of the temperature of the body, and excretes waste products. The excretory function of the skin is always active, but we are unconscious of this activity except on warm days and at times when we perspire freely. In the coldest weather, however, the body throws off what physiologists call the "insensible perspiration." The most important measures for the care of the skin are those intended to insure the activity of the sweat glands, namely, bathing and proper clothing. But before considering these measures, we will describe certain alterations in the skin which cannot escape the notice of the prospective mother, and which she is likely to misinterpret.

On account of the growth of the uterus the abdominal wall is stretched during pregnancy. To a certain degree the skin yields to the distention, but it finally cracks, and lines appear which are commonly called "pregnancy streaks." At first they are delicate and pink or blue in color; later they become white and more extensive.

The streaks indicate the situation of small breaks in the deeper layer of the skin, which is less elastic than the upper layer. They are not painful, and should never cause anxiety. Their size and number vary with the degree of abdominal distention, which in turn depends upon various factors, such as the size of the child and the quantity of amniotic fluid. Although these streaks are most frequently located upon the lower part of the abdomen, they may extend to the outer sides of the thighs; and occasionally appear over the breasts, since they too enlarge during pregnancy. Stretching of the skin, of course, is not confined to pregnancy; consequently, the same kind of streaks often appear in people who are growing stout.

Attempts to prevent or limit the pregnancy streaks prove futile. There is a common belief that they may be prevented by the use of vaselin, goose-grease, mutton-fat, or some one of a variety of lotions; but this teaching is not borne out by experience. None of these applications, however, are harmful, and there can be no objection to using them except that they cause needless soiling of the clothing. After the child is born the streaks fade of their own accord, though they rarely disappear entirely.

In certain localities the skin grows darker during pregnancy. We have already referred to the deepening of the color around the nipple as one of the signs of pregnancy; a similar but much less pronounced discoloration occurs about the navel, which also becomes shallow and may begin to pout in the latter months of pregnancy. About this time, with very few exceptions, there appears a more or less intense brown line which runs downward from the navel in the middle of the abdomen. Sometimes, though not very often, small dark areas, which have been called "liver spots," appear elsewhere over the body. The name is unfortunate, for the spots do not indicate a disorder of the liver.

At present it is generally admitted that alterations in the color of the skin during pregnancy are due to deposits of iron. This mineral substance, among others, as we have learned, is required for the development of the embryo. The child is born with a supply of iron calculated to meet its needs for about a year. Such a reserve is necessary, as Bunge has pointed out, because human milk does not contain enough iron to satisfy the infant's requirements. During pregnancy, therefore, the mother's blood transports iron to the placenta, where it can be absorbed into the child's system; and while being thus transported some of it is deposited in the maternal tissues. The deposits are especially frequent, as I have mentioned, in the middle line of the abdomen, on account of the arrangement of the blood vessels there. Deposits elsewhere may depend upon other conditions; but whatever their cause the pigmentation vanishes a short time after the birth.

Alterations in the color of the skin have no effect upon its excretory function, which, indeed, generally becomes more active during pregnancy. According to one estimate, the average person possesses twenty-eight miles of sweat glands. If these figures are not sufficient to demonstrate the importance of the skin as an excretory organ, surely no one will fail to be impressed by the tragic result which in one case followed throwing all the sweat glands out of action. This was brought about in the case of a young boy whose body was covered with gold leaf to provide entertainment at a Parisian festival. The living statue was not exhibited, however, for shortly after the youth was gilded he became ill and died.

In health more than a pint of water is eliminated through the skin every day, and along with it waste products are removed from the body. Exercise, hot drinks, warm weather, and heavy clothing promote the activity of the sweat glands. Under certain circumstances physicians endeavor to relieve the kidneys by stimulating their patients to perspire freely. It should be clear, therefore, that when a prospective mother naturally perspires it is a good indication. Attempts to stop the perspiration are always ill advised; rather should this function be encouraged by keeping the skin in good condition with baths and warm clothing.

BATHING.—The accumulation of dead skin, grease, dust, and dried perspiration on the surface of the body hinders the actions of the sweat glands. Some of this material is wiped off by the clothing, and more of it is removed by washing with plain water; but the most effectual cleansing results from a liberal use of warm water and soap.

Since the prospective mother must throw off the waste products of the embryo as well as those of her own body, it is obvious that cleanliness is never more important than during pregnancy. For this reason she should take a tepid tub bath or shower every day. It is not necessary that the temperature of the bath be determined with accuracy or that it be always the same; but generally a temperature between 80 and 90 degrees F. is found most agreeable. At this temperature a bath is termed "indifferent," because it is neither stimulating nor depressing; it is employed purely for cleansing the body. Every part of the body should be well soaped, and from ten to fifteen minutes should be given to washing all the exposed surfaces. The best time for such a bath is just before going to bed, though there is no objection to taking it during the day, provided that two hours have passed since the last meal, and that another hour is permitted to elapse before one goes out of doors or undertakes anything that requires exertion.