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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.

Fig. 31.—Height of fundus at each of the ten lunar months of pregnancy.

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.

Fig. 32.—Contour of abdomen at ninth month of pregnancy, or before the waistline drops.

Fig. 33.—Contour of abdomen at tenth month of pregnancy, or after the waistline has dropped.

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.