The role of obstetric factors in perinatal mortality trends.

In the Perinatal Unit of the New Jersey Medical School, Newark the combined neonatal mortality and stillbirth rates declined from more than 51 per 1000 to less than 17 per 1000 between 1971 and 1983. This change is comparable to the reduction of perinatal mortality rates nationwide since the Second World War. Because the improvement in the fetal and neonatal survival rates occurred in a static population and against well identifiable changes in the structure, equipment, policies and management patterns of the obstetric unit, it was possible to assess the impact of various factors upon perinatal outcome. In the environment of this institution adherence to conservative concepts of obstetric management, avoidance of manipulative and extraction procedures, an increase of the rate of cesarean sections from about 7 to 15% and emphasis upon infection control appeared to be the crucially important factors. Antepartum sonography and fetal stress and non-stress testing significantly impacted upon the results. The role of intrapartum electronic monitoring was less clearly definable and seemed to be effective only in the hands of experienced physicians. The results did not seem to be adversely affected by the fact that the program de-emphasized invasive procedures, including fetal scalp pH sampling.