The Prospective Mother | Page 9

will not account for false predictions.
It is generally admitted that second pregnancies average somewhat longer than first pregnancies; one series of statistics indicates that the duration increases slightly with each pregnancy up to the ninth and decreases after that. Pregnancy is protracted more frequently in healthy women than in those who are not, and again more frequently in those who are inactive than in those who work. With twins, contrary to the popular belief, pregnancy is apt to end before, not after, the expected date. The sex of the child, in all probability, has no influence upon the duration of pregnancy.
As we might expect, individuality is also a factor in this problem. Thus, the period of gestation with some women is regularly longer, with others habitually shorter than the accepted average. Until experience has demonstrated their existence, generally, such peculiarities are overlooked. But occasionally they may be detected from knowledge of the interval between the menstrual periods; an unusually long interval between them, for example, would lead us to anticipate a protracted pregnancy.
Any delay after the expected date of birth has arrived taxes the patience of the prospective mother. The fact, however, that more than 280 days have passed since the last menstruation, does not necessarily mean that a patient has gone "over time." Such a question can be decided solely from the weight and length of the child. Judged in this way, comprehensive statistics indicate that once in several hundred cases pregnancy may be fairly called prolonged. Even in these rare instances an examination about the time of the predicted date makes it clear whether pregnancy should be artificially ended or be allowed to proceed to its natural conclusion.


CHAPTER II
THE DEVELOPMENT OF THE OVUM
The Germinal Cells--Fertilization--The First Steps in Development-- The Reaction of the Uterus--The Amniotic Fluid--The Placenta--The Umbilical Cord.
Pregnancy, besides changing the external form of the body, causes sensations--as for example those due to fetal movements--which are so distinctive that they cannot escape notice. These obvious evidences of approaching motherhood naturally lead thoughtful women to wonder about the hidden mechanism of development, a mechanism which, of itself, causes no sensation whatever. It is for this reason, perhaps, that a prospective mother's imagination is so apt to be unusually active, often picturing absurd conditions as responsible for one symptom or another. Those who give free play to the imagination in regard to the formation and progress of the embryo are pretty certain to arrive at erroneous if not grotesque conclusions; for example, they may attribute a protracted pregnancy to the child's having grown fast to the mother, a situation that cannot arise.
Of course it is not essential that a prospective mother should understand what is happening within the womb. And upon those who prefer to be ignorant of the mechanism of development I would not urge another point of view, for not ignorance but the unchallenged acceptance of "half-truths" and of totally incorrect explanations is the chief source of harm. On the other hand, my own experience has taught me that women who wish to know about development should be told the truth. In accord with this is the fact that I never have more satisfactory patients than those who have previously been trained nurses and who, in preparing for that profession, received instruction concerning the reproductive function of human beings.
A description of development, in order to be perfectly clear, must begin with a word about the fundamental structure of the adult body. Everyone knows that the various parts of the body perform different functions; but not everyone, perhaps, realizes that, in spite of their different functions, all the organs of the body are composed of similar structural units, known as cells. Of course, cells are definitely arranged according to the use for which the tissue that they chance to compose may be designed; they have, moreover, distinctive individual peculiarities which can be easily recognized under the microscope; but the essential features of the cells remain the same, wherever they may be located. That is to say, each cell is a minute portion of living matter, or protoplasm, separated from its neighbors by a partition, the cell-membrane; each has its own seat of government, the nucleus, located near its center; and each, to all intents and purposes, leads an individual existence.
THE GERMINAL CELLS.--Many of the cells in the human body are able to produce others of their kind. This they do virtually by growing and splitting in half; cell-division, as this splitting is called, really represents reproduction reduced to the simplest terms. Most cells can do no more than produce units like themselves. The bodies of women contain, however, a type of cell which possesses a far more wonderful power. Provided the requisite conditions for such development are met, these cells are capable of developing into human beings. Each