Maternal age and placenta previa: a population-based, case-control study.

Abstract

Our purpose was to determine if advanced maternal age has an adverse effect on placenta previa independent of other risk factors. A population-based, case-control study was performed with North Carolina vital records from 1988 to 1990, individually matching controls to cases on maternal race, gravidity, parity, previous spontaneous or induced abortion, previous cesarean section, and gestational age at delivery. A multivariate analysis showed that women aged 34 years or older had a two to three times higher risk of placenta previa in relation to women < 20 years old. A clear dose-response pattern was observed with increasing age. Advancing maternal age appears to increase the risk of placenta previa independent of other factors.