Complete rest and physical relaxation are such effective preventive measures that patients with a tendency to have abortions, who have been willing to stay in bed throughout practically the entire period of gestation, have gone through pregnancy without interruption, and been delivered of normal babies at term. As out-of-door exercise is clearly impossible in such cases, it is imperative that the patient keep her room particularly well-ventilated all of the time, and, under the doctor’s direction, have massage or bed exercises. Since abortion seems to be due, so often, to excessively irritable uterine muscle fibres that respond to even slight stimulation, a patient who is known to have difficulty in carrying a child to term is usually advised to avoid the marital relation throughout pregnancy. Some patients with defective uterine lining will have slight bleeding for a long time, possibly throughout the entire period of pregnancy, because a small area of the placenta has separated, leaving, however, a sufficiently large attached area to nourish the fetus. Such women should, of course, be under a doctor’s care and sedulously avoid all shocks to the uterine musculature, for the separated area may very easily be increased to such a size that the fetus will be unable to secure adequate nourishment, and die as a result. And the mother’s life, too, may be endangered by hemorrhage from the separated surfaces. To sum up in a word, we may almost say that, after pregnancy has begun, preventive treatment consists of rest and avoiding physical shocks, particularly during the first sixteen or eighteen weeks and at the time when menstruation would occur were the woman not pregnant. =Treatment=, in the different degrees of abortion, employed by most physicians, is usually along some such lines as the following: =1. Threatened.= A threatened abortion is one in which there is some loss of blood, associated with pain in the back and lower abdomen, but without expulsion of the products of conception. The treatment, as a rule, is absolute rest in bed and the administration of powerful sedatives. =2. Incomplete.= An incomplete abortion is one in which the fetus is expelled but the placenta and membranes remain in the uterine cavity. The treatment is removal of the retained tissues, followed by the same care that is given during the normal puerperium. Prompt action in completing the delivery is important because of the hemorrhage that usually persists until the uterus is entirely emptied of its contents. Since the pregnant uterus is very soft, the retained membranes are more often removed manually than instrumentally, for a curette may be very easily pushed through the uterine wall, and peritonitis would be likely to follow.