Signs and Symptoms of Pregnancy. Unfortunately for all parties concerned, the exact duration of pregnancy has never been ascertained, since there is no way of knowing when the ovum is fertilized, the moment which marks the beginning of pregnancy.

It is obviously impossible, therefore, to foretell exactly the date of confinement. But labor usually begins about ten lunar months, forty weeks or from 273 to 280 days after the onset of the last menstrual period.

Thus the approximate date of confinement may be estimated by counting forward 280 days or backward 85 days from the first day of the last period. Or what is perhaps simpler, and amounts to the same thing, one may add seven days to the onset of the last period and count back three months. For example, if the last period began on June third, the addition of seven days gives June tenth, while counting back three months indicates March tenth as the approximate date upon which the confinement may be expected.

This is probably as satisfactory as any known method of computation, but at best it is only approximate, being accurate in about one case in twenty. But it comes within a week of being correct in half the cases, and within two weeks of the date in eighty per cent of all pregnancies.

Another method sometimes employed by obstetricians is to estimate the month to which pregnancy has advanced by measuring the height of the fundus, and thus forecasting the probable date of confinement. It is generally agreed that the ascent of the fundus is fairly uniform and that at the fourth month it is half way between the symphysis and umbilicus; at the sixth month, on a level with the umbilicus; at the seventh month, three fingers’ breadth above; at the eighth month, six fingers above the umbilicus and at the ninth month just below the xiphoid. At the tenth month, or term, the fundus sinks downward to about the position it occupied at the eighth month. (Figs. 31, 32 and 33.)

This method, however, is measuring by months, not days, and leaves a wide margin for conjecture as to the exact date.

Still another method is to count forward 20 or 22 weeks from the day upon which the expectant mother first feels the fetus move. As we shall see presently, this experience, termed “quickening,” usually occurs about the 18th or 20th week, but is so irregular that it is unreliable as a basis for computation.

The possibility of estimating the date of confinement is still further complicated by the fact that there is evidently considerable variation in the length of entirely normal pregnancies. Many healthy children are born before ten lunar months have elapsed, while more deliveries occur after than on the expected date. The first pregnancy is usually shorter than subsequent ones, and women who are well nourished and well cared for have longer pregnancies, as a rule, than those less favored.

Although the symptoms of pregnancy have been observed throughout the ages by women who have borne children, and accoucheurs of one sort and another who have attended them, a positive diagnosis at an early stage of this condition is sometimes still baffling to the most experienced obstetricians.

So many symptoms of pregnancy are known to women the world over, that an expectant mother frequently recognizes her pregnant state at a very early date. This is particularly true of women who have previously borne children. But as these same symptoms closely resemble those of other conditions, they are not infrequently ascribed to impaired health, with the result that the pregnancy is not discovered until it is well advanced, and then sometimes only by accident. And one even hears of an occasional case in which a woman is entirely unaware of her condition until she goes into labor.

The converse is also true, for women sometimes erroneously believe themselves pregnant because of the appearance of well recognized symptoms, which are due to other causes. This condition is known as pseudocyesis, or spurious pregnancy, and is usually found in women approaching the menopause or in young women who intensely desire offspring. It is a pathetic occurrence, and the patient is usually so tenacious of her belief in her approaching motherhood that the obstetrician dispels it only with great difficulty.

For all of these and other reasons it is customary to divide the signs and symptoms of pregnancy into three groups, under self-explanatory headings, namely: presumptive symptoms, and probable and positive signs. Although it is never within the province of a nurse to make a diagnosis, it is important that she be familiar with symptoms. In obstetrics this seems to be particularly true, and especially so if the nurse be engaged in prenatal work or in any branch of public health nursing that brings her in touch with possible or expectant motherhood. The wider her grasp of obstetrical knowledge, the more helpful and reassuring can be her relation to her patient. To this end, therefore, we will take up the most reliable symptoms and signs of pregnancy.

The presumptive signs, which consist largely of subjective symptoms observed by the patient herself, are as follows:

1. Cessation of menstruation. This is usually the first symptom noticed. A period may be omitted from any one of several causes, as has been explained in Chap. II but in a healthy woman of the childbearing age, whose menses have previously been regular, the missing of two successive periods after intercourse is a strong indication of pregnancy.

2. Changes in the breasts. These also occur early. The breasts ordinarily increase in size and firmness, and many women complain of throbbing, tingling or pricking sensations and a feeling of tension and fullness. The breasts may be so tender that even slight pressure is painful. The nipples are larger and more prominent, while both they and the surrounding areolæ grow darker. The veins under the skin are more apparent and the glands of Montgomery larger. If in addition to these symptoms it is possible to express a pale yellowish fluid from the nipples of a woman who has not had children, pregnancy may be strongly suspected. But practically all of these symptoms may be due to causes other than pregnancy, and, in the case of a woman who has borne children, milk may be present in the breasts for months, or even years, after the birth of a child.

3. “Morning sickness,” as the name suggests, is nausea, sometimes accompanied by vomiting, from which many pregnant women suffer immediately upon arising in the morning. It varies in severity from a mild attack when the patient first lifts her head to repeated and severe recurrences during the day, and even into the night. More frequently, however, the discomfort passes off in a few hours. When the vomiting persists, it is termed “pernicious vomiting” and is usually accepted as a possible symptom of a reflex, toxic or neurotic condition, all of which will be discussed with the complications of pregnancy. Morning sickness may begin immediately after conception, but sets in as a rule about the sixth week and continues until the third or fourth month. It occurs in about half of all pregnancies and is particularly common among women pregnant for the first time. But on the other hand, it must be borne in mind that many non-pregnant women suffer from nausea in the morning; many women go throughout the entire period of gestation without any such disturbance, while others are entirely comfortable in the morning and nauseated only during the latter part of the day.

4. Frequent micturition. There is usually a desire to void urine frequently during the first three or four months of pregnancy, after which the tendency disappears, but recurs during the later months. The inclination may be due in part to nervousness, but is largely caused by pressure exerted by the enlarging uterus upon the bladder, and not to any functional disturbance of the kidneys, as is sometimes believed. Pressure on the outside of the bladder gives much the same sensation as is experienced when the bladder is distended with urine. After the uterus rises from the pelvic cavity into the abdomen, it no longer crowds the bladder, until it drops during the last month or six weeks, when it again presses upon this organ and cause a desire to void.

5. Increased discoloration of the pigmented areas of the skin, and also of the mucous membranes, is another early symptom of pregnancy. In addition to the deepened tint of the nipples and surrounding areolæ, the so-called linea nigra appears upon the abdomen, extending from the pubis toward the umbilicus. There are also the dark bluish or purplish appearance of the vulval and vaginal linings; the yellowish, irregularly shaped blotches which sometimes appear on the face and neck, known as chloasma: dark circles under the eyes and the striæ on the abdomen.

6. “Quickening” is the widely used term which designates the mother’s first perception of the fetal movements. It occurs about the eighteenth or twentieth week, and is regarded by some obstetricians as a positive and by others as merely a strongly presumptive sign of pregnancy. The sensation is likened to a very slight quivering or tapping, or to the fluttering of a bird’s wings imprisoned in the hand. Beginning very gently, these movements increase in severity as time goes on until they become very troublesome toward the latter part of pregnancy, amounting then to sharp kicks and blows. Women who have had children can usually be relied upon to distinguish between quickening and the somewhat similar sensation caused by the movement of gas in the intestines, but a woman pregnant for the first time may be deceived.

There are many other possible symptoms of pregnancy, but their value is very uncertain. Even the ones described above are not entirely dependable, but if two or more of them occur coincidently, they probably indicate pregnancy. Dr. Slemons sums it up by saying, “If, for example, menstruation has previously been regular and then a period is missed, the patient has good reason to suspect she is pregnant; if the next period is also missed and meanwhile the breasts have enlarged, the nipples darkened, and the secretion of colostrum has begun, it is nearly certain that she is pregnant; whether morning sickness and the desire to pass urine frequently are present is of no importance.”^[2]

The probable signs of pregnancy are chiefly discoverable by the physician after careful examination. They also are numerous and uncertain, but there are four which are considered fairly trustworthy.

1. Enlargement of the abdomen, which is first in order of importance, is apparent about the third month. At this stage the growing uterus may be felt through the abdominal wall as a tumor which steadily increases in size as pregnancy advances. Rapid enlargement of the abdomen in a woman of child-bearing age, therefore, may be taken as fair, but not positive, evidence of pregnancy. But too much reliance cannot be placed in this sign, as the abdomen may be enlarged by a tumor, fluid or a rapid increase in fat.

2. Changes in the size, shape and consistency of the uterus which take place during the first three months of pregnancy are very important indications. These are discoverable upon vaginal examination, which shows the uterus to be more ante-flexed than normal, considerably enlarged, somewhat globular in shape and of a soft, doughy consistency. About the sixth week the so-called Hegar’s sign is perceptible through bimanual examination, the fingers of one hand being pressed deeply into the abdomen, just above the symphysis and two fingers of the other hand passed through the vagina until they rest in the posterior fornix, behind the cervix. The lower segment of the uterus, which may be felt between the finger tips of the two hands, is extremely soft and compressible. This sign, named for the man who first described it, is one of the most valuable signs in early pregnancy.

3. Softening of the cervix occurs, as a rule, about the beginning of the second month. In some cases, such as certain inflammatory conditions and in carcinoma, this sign may not appear.

4. Painless uterine contractions, called Braxton Hicks from their first observer, begin during the early weeks of pregnancy and recur at intervals of five or ten minutes throughout the entire period of gestation. The patient is not conscious of these contractions, but they may be observed during the early months by bimanual examination, and subsequently by placing the hand on the abdomen. One feels the uterus growing alternately hard and soft as it contracts and relaxes.

But all of the probable signs of pregnancy, like the presumptive symptoms, may be simulated in non-pregnant conditions; hence the appearance of any one of them alone may not be deeply significant. But two or more occurring coincidently constitute strong evidence of pregnancy.

The positive signs of pregnancy, of which there are three, are not apparent until the 18th or 20th week, and all emanate from the fetus.

1. Hearing and counting the fetal heart beat is unmistakable evidence of pregnancy. The sound of the fetal heart beat is usually likened to the ticking of a watch under a pillow. The rate is from 120 to 140 per minute, being about twice as fast as the maternal pulse. So long as its rhythm is regular, however, the rate may drop to 100 or increase to 160 beats per minute without being considered abnormal, or indicative of trouble with the fetus.

2. Ability to palpate the outline of the fetus is also a positive sign of pregnancy, if the head, breech, back and extremities are unmistakably made out through the abdominal wall.

3. Perception of active and passive movements of the fetus is accepted as a third incontrovertible sign of pregnancy. There is some difference of opinion concerning the value of “quickening” alone as a positive sign of pregnancy. But if the fetal movements are also perceptible by the obstetrician through the mother’s abdominal wall or by vaginal examination, there can be no doubt about the diagnosis. The movements felt by placing the hand upon the abdomen are termed active movements, while the passive movements result from internal or external ballottement. Ballottement is accomplished by giving a sharp or sudden push to the head or an extremity, and feeling it rebound in a few seconds to its original position. Passive movements may be felt early in the fourth month, and active movements after the 18th or 20th week.

PHYSIOLOGY OF PREGNANCY

A general understanding of the physiology of pregnancy is indispensable to an appreciation of the importance of observing the present-day teachings about the hygiene of pregnancy. Upon this, in turn, must rest intelligently administered prenatal care, one of the most important branches of obstetrics.

The physiology of pregnancy really represents an adjustment of the various functions of the maternal organism, which are altered to meet the demands made upon the mother’s organs by the body which is developing, growing and functioning within hers. These adjustments are in the nature of an emergency service, since they come into existence and operate only while needed, which is during pregnancy, and promptly disappear when the need for them ceases with the birth of the child. The mother’s body then begins to return to its normal, non-pregnant state, which, with the exception of the breasts, which function for nine or ten months, is accomplished in a few weeks.

But in addition to the normal changes in physiology in the course of pregnancy, there are frequently abnormal changes, too, which may be symptoms of grave complications. The detection of these symptoms, and the employment of treatment which they indicate, constitute one of the most valuable aspects of prenatal care.

Although, as might be expected, the alterations in the structure and functions of the maternal organism are most marked in the generative organs, there are definite changes in other and remote parts of the body as well. And there are adjustments in metabolism, which, though not wholly understood, are now widely recognized as important. It is pretty generally believed that as a direct, result of pregnancy, certain substances are created, possibly by the corpus luteum, which circulate in the blood and definitely influence the maternal functions. It is possible that a development of the present imperfect knowledge of these substances will result ultimately in the discovery of a blood reaction which will serve to diagnose pregnancy in an early stage.

At present, we know that, in spite of the creation of an infant body weighing upwards of seven pounds, a placenta weighing more than a pound, together with an increase of about two pounds in the weight of the uterine muscle, all in the short span of nine months, the expectant mother has to eat very little more during this period than she ordinarily does to maintain her own bodily functions. This suggests a highly developed economy in the use of nutritive material by maternal cells.

We also know that the mother excretes waste materials for the fetus and must assume that this requires an increased, or adjusted, functional activity of her excretory organs, the skin, lungs and kidneys. Moreover, the secretory activity of the previously inactive mammary glands, in spite of their remoteness from the pelvis, suggests a nervous or chemical stimulation, or both, which occurs only during pregnancy.

The changes in the uterus itself, however, are unquestionably the most marked that take place during the period of gestation. Those that relate to the lining have been described in a previous chapter. The change and growth in the muscle wall are amazing. New muscle fibres come into existence; those already there increase greatly in size and there is a marked development of connective tissue.

The actual substance of the uterus is so increased that it is converted from an organ weighing two ounces into one weighing two pounds. From a firm, hard, thick walled, somewhat flattened body in its non-pregnant state, the gravid uterus assumes a globular outline and grows so soft that the fetus may be felt through the walls.

During the first few months the uterine walls increase in thickness, but later they grow progressively thinner, until by the end of pregnancy they are only about 5 millimetres thick.

This early growth of the uterus is doubtless brought about by general systemic changes rather than by the presence of the contained embryo. Evidence of this is found in the case of tubal pregnancies when there is a definite enlargement of the uterus during the early weeks. After the third month, however, the growth of the uterus is apparently due to pressure which the growing fetus makes on the uterine walls.

The cervix does not enlarge as a result of pregnancy, but it loses its hard cartilaginous consistency, becoming quite soft, and the secretion of the cervical glands is much more profuse.

The changes in the vagina are chiefly due to increased vascularity. The blood vessels are actually larger, the products of the glands are greatly increased and the normal pinkish tint of the mucous lining deepens to red or even purple.

The most important changes in the tubes and ovaries is in their position because of their being carried up from the pelvis by the enlarging uterus into the abdominal cavity. Although they increase in vascularity, ovulation is ordinarily suspended during pregnancy.

The abdomen as a whole changes in contour as it steadily enlarges, and the skin and underlying muscles are somewhat affected as a result. The tension upon the skin is so great that it may rupture the underlying elastic layers which later atrophy and thus produce the familiar striæ of pregnancy, known variously as the striæ gravidarium and the linea albicantes. Fresh striæ are pale pink or bluish in color, but after delivery they take on the silvery, glistening appearance of scar tissue, which they really are.

In a woman who has borne children, therefore, we find both new and old striæ; those resulting from former pregnancies being silvery and shining, while the fresh tears are pink or blue. Striæ may be found also on the breasts, hips and upper part of the thighs, and as they are of purely mechanical origin, are not necessarily associated with pregnancy alone. They may result from a stretching of the skin by ascites, a marked increase in fat or an abdominal tumor.

The same distension that causes striæ sometimes causes a separation of the recti muscles. This separation, known as diastasis, is sometimes slight but frequently very marked, the space between the muscles being easily felt through the thinned abdominal wall.

The umbilicus is deeply indented during about the first three months of pregnancy. But during the fourth, fifth and sixth months the pit grows steadily shallower, and by the seventh month it is level with the surface. After this it may protrude, in which state it is described as a “pouting umbilicus.”

The increased pigmentation at the umbilicus and in the median line is scarcely to be classified among the abdominal changes, as the skin elsewhere presents the same discolored appearance. The degree of pigmentation varies with the complexion of the individual, as blondes may be but slightly tinted while the discolored areas on a brunette may be dark brown, sometimes almost black.

The changes in the breasts during pregnancy were practically all included in the enumerated signs and symptoms of pregnancy. They increase in size and firmness and become nodular; the nipple is more prominent and together with the surrounding areolæ, grows much darker; the glands of Montgomery are enlarged; the superficial veins grow more prominent, and after the third month a thin, yellowish fluid can be expressed from the nipples. This fluid, called colostrum, consists largely of fat, epithelial cells and colostrum corpuscles and differs from milk, in its yellowish color, and in the fact that it coagulates like the white of an egg when boiled. The previously quiescent mammary glands develop very early in pregnancy an ability to select from the blood stream the necessary materials to produce a secretion. Colostrum is the product of their activity until about the third day after delivery, when milk appears.

Changes in the cardio-vascular system are among those which are not altogether understood, and it is still a moot question as to whether or not there is an actual increase in the amount of maternal blood during pregnancy. But results of the most recent investigations suggest that there is a definite increase in both the cells and the plasma. This increased amount circulating through the heart subjects it to a certain amount of strain, with the result that the organ is slightly hypertrophied and the pulse pressure is higher.

The respiratory organs do not show any marked alterations. The upward pressure of the enlarging uterus gradually shortens the height of the thoracic cavity, but if it grows sufficiently wide in compensation, there is no decrease in the capacity of the lungs. If this does not occur, the patient may suffer from shortness of breath. The larynx is sometimes reddened and edematous, a fact which explains the damaging effects which child-bearing may have upon the voice of singers.

Changes in the digestive tract during pregnancy are the morning sickness already described, and constipation. The latter is suffered by at least one half of all pregnant women, and is due chiefly to pressure of the uterus on the intestines, though impaired tone of the stretched abdominal muscles may be a factor. This condition is most troublesome during the latter part of pregnancy. There also may be gastric indigestion causing acidity, flatulence and heartburn, and intestinal indigestion giving rise to diarrhea and cramp-like pains. The appetite may be very capricious during the early weeks, and become almost ravenous later on.

Changes in the urinary apparatus include frequency of micturition mentioned among the symptoms of pregnancy.

The changes in the bony structures of the pregnant woman are characterized by partial decalcification. This is accounted for by the fact that the developing fetus requires a definite amount of calcium in the formation of its osseous structures, and unless the expectant mother absorbs an adequate quantity from her food, it must be extracted from the bones and similar structures, such as the teeth. Her bones and teeth accordingly grow softer, and we have the well-known adage, “for every child a tooth,” as well as the fact that fractures during pregnancy unite very slowly. There are also the softened cartilages which were referred to in connection with the anatomy of the pelvis. A part of the softening of the pelvic cartilages, however, is due to a temporarily increased blood supply. As will be explained in the chapter on nutrition, this partial decalcification of the mother is entirely unnecessary, and the newer knowledge of nutrition points the way to its prevention.

The skin changes consist chiefly in the appearance of striæ and the increased pigmentation to which reference has already been made. There is also an increased activity of the sebaceous and sweat glands and the hair follicles, the latter sometimes resulting in the hair becoming much more abundant during the period of gestation. Although the pigmented areas on the breasts and abdomen never quite return to their original hue, the chloasmata, sometimes called the “masque des femmes enceintes,” practically always disappear and leave no trace, a fact that is frequently a comfort to an expectant mother.

The carriage is somewhat affected during pregnancy because the increased size and weight of the abdominal tumor shifts the centre of gravity. In an effort to preserve an upright position the woman throws back her head and shoulders and finally assumes a gait that may be described as a waddle, particularly noticeable in short women.

Temperature changes are probably not caused by pregnancy per se, though some authorities believe that there is normally a slight elevation during the latter part of the day.

Mental and emotional changes are usually included among the alterations which occur during pregnancy, but the present status of psychiatry suggests that this may not be altogether true. It is a fact that many pregnant women show marked mental and emotional unbalance, but as yet there seems to be no evidence that these states are inherently due to pregnancy, though the same condition may recur in the same woman each time that she is pregnant.

We shall consider this important subject more at length in the chapter on mental hygiene, so it may be enough simply to say at this juncture that, in a sensitively strung or uncertainly poised woman, the state of being pregnant may be merely the last straw, so to speak, that upsets her equilibrium; and that some other experience, which would be an equal strain upon her slender ability to make adjustments, would result in exactly the same mental or emotional distortion, just as certain physical signs in pregnancy may be produced also in the non-pregnant state, and are not, therefore, necessarily inherent to the gravid state.

Changes in the ductless glands are in much the same category. Functional disturbances of these glands occurring at any time may give rise to great irritability, excitability or to other mental symptoms. A non-pregnant woman with even a very slight degree of hyperthyroidism, for example, may be noticeably unstable mentally or emotionally. Since there is evidently an inter-relation and inter-dependence of the functions of the ductless glands, and since ovulation, the function of one of these glands, is suspended during pregnancy, we can readily believe that other glands would undergo changes as a result. Alterations in the thyroid are particularly apparent as it becomes enlarged and more active in the majority of pregnant women, as does also the anterior lobe of the pituitary body. This increased activity may tend to compensate for the suspended function of the ovaries. But the alterations in the functions of the other glands, compensatory though they be in part, apparently produce much the same sort of nervous symptoms that they are capable of producing in a non-pregnant woman.

Taking the condition as a whole, pregnancy is usually characterized by an improved state of health. During the first few months there may be lassitude and loss of weight, but the latter part of the period is notable for an unusual degree of general well being and for an increase in flesh over the entire body, which may amount to as much as twenty-five or thirty pounds.

About fifteen pounds of the increased weight is lost at the time of labor and a still further reduction occurs during the succeeding weeks when the mother’s body returns approximately to its original condition. But it sometimes happens that the improved state of nutrition acquired during pregnancy becomes permanent.