Racial differences in the etiology of abruptio placentae.

Of 13,500 deliveries in a 6-year period, 326 cases of antepartum hemorrhage (2.4%) were encountered. Fifty-six (0.42%) of these patients had abruptio placentae while 130 (0.96%) had placenta previa. An inverse ratio of placenta previa and abruption placentae was observed in this study, which may be due to a racial difference--probably a result of the late onset of preeclampsia among Nigerians. A high perinatal mortality of 643/1000, influenced mainly by the high prematurity rate, was observed; cesarean section resulted in the lowest perinatal mortality (154/1000). There was one maternal death, giving a maternal mortality rate of 18/1000.