Although many conditions that result in invalidism or death occur during labor or the puerperium, they have their beginnings during pregnancy. Their prevention, then, or early recognition, followed by prompt and efficient treatment, will avert many of the dreaded complications and emergencies associated with childbearing. In order to prevent these disasters it is necessary to supervise the expectant mother and care for her from early in pregnancy—from the time of conception if possible—until the onset of labor, and this is prenatal care. It may be divided into instruction, examinations and observations, as follows: 1. a. Teaching the expectant mother the principles of personal hygiene, as especially adapted to meet her needs, and helping her to adopt them; b. Describing to her the more apparent, normal changes of pregnancy which she is likely to notice and perhaps not understand, and also the common symptoms of complications which she may detect and should report; 2. The doctor’s preliminary examination, early in pregnancy, comprising a study of the size, shape and proportions of the pelvis, and later their relation to the size and mouldability of the baby’s head; a Wassermann test for syphilis; urinalysis and measuring the blood pressure. In addition to these, a complete physical survey is made, consisting of examinations of the heart, lungs, breasts, abdomen, a vaginal smear for gonorrhea, and the patient’s height, weight and temperature; 3. Constant watching for early symptoms of the complications of pregnancy, with speedy treatment of such symptoms when they appear, and relieving the common discomforts of pregnancy; making observations upon the presentation and size of the fetus, later in pregnancy, in order to plan ahead of time for the delivery, if the patient’s condition makes this advisable. Prenatal care of this character is essentially preventive for both the mother and the new-born baby. We gain a faint impression of what it may prevent when we learn that year after year, about 17,000 young women die in the United States from causes associated with childbirth, which are known to be largely preventable (during 1918 the number was 23,000); and that each year about 112,000 babies are born dead, and 100,000 of those born alive perish during the first month of life, also from causes which are largely controllable.