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.