Despite the availability of health resources to provide prenatal and delivery care for all pregnant women in the Federal District, the maternal mortality ratio is extremely high. Based on the study of all the maternal deaths which occurred in the Federal District during 1988 and the first semester of 1989 (n = 433), a ratio of 11.4 deaths per 10,000 registered live births was estimated. This is almost twice as high as the ratio reported through vital statistics. The maternal mortality ratio is higher among women delivered in public assistance hospitals as compared with those delivered in social security hospitals. This is due to the high percentage of women arriving with severe complications and to the lower standards of obstetric care in the former. About 75% of the deaths were due to one of the following causes: hypertensive disease of pregnancy, hemorrhage and infection. A detailed study of hospital records undertaken by a maternal mortality committee revealed that 85% of the deaths were preventable with the technology and resources available. The committee identified errors in medical judgment as the main factor involved in the chain of causation leading to potential preventable deaths.