The Prospective Mother, a Handbook for Women During Pregnancy

by J. Morris Slemons

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.