Characteristics of patients with placenta previa and results of "expectant management".

To determine the differences between pregnancies complicated by placenta previa and those without placenta previa, the characteristics of 31,070 consecutive deliveries at one institution were analyzed. The philosophy of "expectant management" of the premature fetus and frequent use of cesarean section was utilized in the 185 patients with placenta previa. A higher proportion of these patients were multiparous, were older, had had previous abortions, and were carrying a male fetus or twins. The fetal and placental weights in these patients were similar to those in other patients throughout pregnancy. Rates of prematurity, antepartum and intrapartum fetal death, neonatal death, congenital abnormality, and low Apgar scores were higher among patients with placenta previa. Data were compiled in a manner that allows the obstetrician to: (1) evaluate the fetal weight and expected fetal growth; (2) estimate the probability that his patient will deliver prematurely and will deliver within the next one-, two-, or four-week interval; (3) determine the relative risks to the fetus prior to labor, during labor, and in the neonatal period at each stage of gestation.