CHAPTER XIV
THE PHYSIOLOGY OF THE PUERPERIUM
The puerperium[8] is ordinarily regarded as comprising the five or six weeks immediately following delivery. During this period the mother’s body undergoes various changes which restore it very nearly to its pre-pregnant state, leaving the patient in a normal, healthy condition. The most important of these changes are involution of the uterus, loss of weight and improvement in tone of the abdominal and perineal muscles. The alterations which produce this restoration are normal physiological processes, but mismanagement or lack of care while they are taking place may result in serious complications; these may be immediate or remote, such as hemorrhage and infection or chronic invalidism.
Recognition of these dangers, and the possibility of preventing them, is responsible for the present custom of obstetricians to watch over their patients during the puerperium. This is in sharp contrast to the old practice of the doctor’s visiting the puerperal woman only when there was a complication so apparent that he was summoned.
The precautions and the care which the doctor takes of his patient after delivery involve intelligent and watchful nursing. In order to give this the nurse must understand something of the normal physiology of the puerperium, just as she did in pregnancy and labor. Otherwise she may not be able to distinguish evidences of normal changes from symptoms of complications.
=Involution.= Considerable attention is centred in the remarkable atrophic changes that take place in the uterus during the puerperium, for it is upon their being normal that the patient’s recovery and future well-being so largely depend. Immediately after delivery the uterus weighs about two pounds; is from seven to eight inches high; about five inches across and four inches thick. The top of the fundus may be felt above the umbilicus, and the inner surface, where the placenta was attached, is raw and bleeding. At the end of six or eight weeks the uterus has descended into the pelvic cavity and resumed approximately its original position and size, and its former weight of two ounces; a new lining has developed from the few glands which have not been cast off in the discharges.
This rapid diminution in the size of the uterus is termed involution and is accomplished by means of a process of self-digestion or _autolysis_. The protein material in the uterine walls is broken down into simpler components which are absorbed and eventually cast off largely through the urine. This change and absorption of uterine tissues is similar to the resolution that takes place in a consolidated lung in pneumonia.
Since satisfactory involution is necessary to the patient’s future health, its progress should be watched with deep concern and interest, and all possible effort made to promote it; firm consistency of the uterus and a steady descent into the pelvis and normal lochia being the chief evidences of satisfactory involution. There is evidently a close relation between the functions of the breasts and of the uterus during the puerperium, and as a rule involution accordingly progresses more normally in women who nurse their babies than in those who do not.
The so-called “after-pains” are also affected by nursing, being more severe as a rule when the baby is at the breast than at other times. These pains are caused by the alternate contractions and relaxations of the uterine muscles and are more common in multiparæ, than in primiparæ, because the muscles of the former have somewhat less tone than the latter and therefore tend to relax, and then contract, whereas the better muscle tone of the primipara tends to keep the uterus steadily contracted.
These after pains usually subside after the first twenty-four hours, though they may persist for three or four days. They may amount to little more than discomfort, but not infrequently are so severe as to require the administration of sedatives. Persistent after pains may be due to retained clots.
The cervix, vagina and perineum which have become stretched and swollen during labor, gradually regain their tone during the puerperium, and the stretched uterine ligaments become shorter as they recover their tone, finally regaining their former state. Until the ligaments and the pelvic floor and abdominal wall are restored to normal tonicity the uterus is not adequately supported and therefore may be easily displaced.
=The lochia= consists of the uterine and vaginal secretions and the blood and uterine lining which are cast off during the puerperium. During the first three or four days this discharge is bright red, consisting almost entirely of blood, and is termed the _lochia rubra_. As the color gradually fades and becomes brownish it is called the _lochia serosa_. After about the tenth day, if involution is normal, the discharge is whitish or yellowish and is designated as the _lochia alba_. The total amount of the lochial discharge has been variously estimated at from one to three pints, being more profuse in multiparæ than primiparæ, and in women who do not nurse their babies. Under normal conditions the discharge is profuse at first, gradually diminishing until it entirely disappears by the end of the puerperium. There may be small amounts of blood retained during the first day or two and expelled later as clots, without any serious significance, and there may be a pinkish discharge after the patient gets up for the first time, but if the lochia is persistently blood-tinged it may be taken as an indication that the uterus is not involuting as it should.
The normal characteristic odor is flat and stale. A foul odor, no odor at all or a marked decrease in the amount of the discharge is suggestive of infection.
=Loss of Weight.= One of the striking changes during the puerperium is the loss in weight, due largely to three factors: the elimination of fluids from the edematous tissues; the decrease in the size of the uterus and the escape of vaginal and uterine secretions, termed the lochia. The smaller amount of food taken during the first few days post-partum also may be a factor.
This loss in weight is extremely variable, fat women naturally losing more than thin women and those who nurse their babies losing more than those who do not.
Dr. Edgar estimates that the loss through the lochia amounts to something over three pounds, and the loss through fluids from the tissues, from nine to ten pounds. According to Dr. Slemons, the loss in fluids equals about 1/10th of the patient’s weight at the beginning of the puerperium, while all agree that the uterus decreases about two pounds in weight. All told, then, the patient may normally lose from twelve to fifteen pounds during the puerperium. This loss may be somewhat controlled, however, by a suitable diet, and under most conditions the patient should return to not less than her pre-pregnant weight by the end of the sixth or eighth week.
=Menstruation.= Although in the ideal course of events, the mother does not menstruate while nursing her baby, that is, for eight to ten months, Dr. Slemons estimates that about one-third of all nursing mothers begin to menstruate about two months after delivery, while according to Dr. Edgar one-half of those who do not nurse their babies begin to menstruate in six weeks after delivery.
Menstruation is more likely to return early in primiparæ than in multiparæ. Patients sometimes wonder whether this early discharge is menstrual or lochial, and though they can not tell, a physician can easily decide by examination, and it is important that he be given the opportunity to do so. A nursing mother may menstruate once and then not again for several months or a year; or she may menstruate regularly and nurse her baby satisfactorily at the same time, though menstruation is usually regarded as unfavorable to lactation.
=Lactation.= During the first two or three days after the baby is born, the breasts secrete a small amount of yellowish fluid called colostrum, which differs from milk chiefly in that it contains less fat and more salts and serum-albumen than milk and in the fact that it coagulates upon boiling. About the third day after delivery, the meagre amount of colostrum is replaced by milk and as it increases rapidly in amount, the breasts usually become tense and swollen at this juncture, and sometimes very painful; but this turgidity usually subsides after a day or two.
The function of the breasts, that of secreting milk, is definitely stimulated by the baby’s suckling and will not continue for more than a few days without this stimulation, a fact to be remembered if it is desirable for any reason to dry up the breasts.
The ideal condition is for the breasts to secrete a quantity and quality of milk which will adequately nourish the baby for eight or ten months. The reverse of this condition is sometimes found in very young or in elderly women, or in very fat or frail, undernourished women.
Ovulation is usually suspended during lactation, but a mother may become pregnant a few weeks after delivery even while nursing her baby, though the quality of her milk is likely to be unfavorably affected by the pregnancy. But, as has been explained, the return of menstruation does not necessarily exert as unfavorable an influence upon lactation as was formerly believed.
=Abdominal Wall.= The abdominal wall is usually overstretched during pregnancy, and immediately after labor when the tension is removed, the skin lies in folds and the entire wall is soft and flabby. The normal and desirable course is for the muscles gradually to regain their tone; for the excess of fat to be absorbed and the walls to approach their original state in the course of a few weeks. The striæ usually remain, and the muscles sometimes fail to regain their tone, as for example when pregnancies follow each other in rapid succession or when there has been excessive distension. In such cases there is likely to be the pendulous abdomen so often seen in multiparæ, and a diastasis, or separation of the rectus muscles.
=Digestive Tract.= During the first day or two after delivery the mother may have very little appetite but she is usually very thirsty. She will almost inevitably be constipated, because of the loss of intra-abdominal pressure; the sluggishness of the intestines acquired during pregnancy; her recumbent position, lack of exercise and the fact that she is taking relatively less food than usual and that her bowels were freely evacuated at the onset of labor.
=Temperature.= The temperature often rises to about 99° F. immediately after labor but it should drop to normal in a few hours and practically remain so. For various causes, some of which are unexplained, the temperature will not infrequently be slightly above normal at times during the first few days of the puerperium, without the patient’s seeming to suffer any ill effects. But the fairly general agreement among obstetricians seems to be that a temperature of 100.4° F. is the upper limit of normality and that infection is to be suspected if it reaches that point and remains there for twenty-four hours.
=Pulse.= The normal pulse rate is usually slower during the puerperium, being about 60 or 70 beats to the minute, and is referred to as puerperal _bradycardia_. It is thought that this is due to the absolute rest in bed and the decreased strain upon the heart after the birth of the baby.
=Skin.= There is usually profuse perspiration during the first few days, while the elimination of fluids is most active, but it gradually subsides and becomes normal by the end of a week. The perspiration sometimes has a strong odor and there is not infrequently an appreciable amount of desquamation.
=Urine.= Many patients find it difficult, even impossible, to void urine during the first several hours after delivery because of the removal of intra-abdominal pressure; the recumbent position and the swelling and bruised state of the tissues about the urethra. The bladder is likely to be less sensitive than usual and the patient will be able to retain an abnormally large amount of urine for several hours without discomfort, or desire to void.
The output of urine during the first few days is greater than normal, and there is also a considerable increase in the amount of nitrogen excreted, beginning two or three days after delivery. This is evidently derived from the broken down proteins in the uterine wall, and the excess gradually subsides as involution progresses, and disappears by the time the uterus descends into the pelvis.
When one considers the severe ordeal that the young mother has just passed through, her recovery and return to a normal state are surprisingly rapid, when she is given good care.