Risk factors for placenta praevia in southern Nigeria

Objective : To determine the risk factors for placenta praevia in Ile-Ife, southern Nigeria. Design : A prospective case control study. Setting : A tertiary center - Obafemi Awolowo University Teaching Hospital, Ile-Ife, southern Nigeria. Subjects : One hundred and thirty six patients with confirmed placenta praevia constituted the cases. Controls consisted of one hundred and thirty six patients who delivered at term immediately after each indexed case and did not have placenta praevia. Results : Cases and controls were similar in terms of twin deliveries (P=0.72) and past history of uterine surgery (P=0.47). After adjusting for confounders, factors associated with risk of placenta praevia were history of retained placenta [OR=6.7(95% CI 1.2- 36.6)], previous caesarean section [OR=4.7, (95% CI 1.9-11.4)], previous abortion [OR=2.9 (95% CI 1.1-5.1)], grand multiparity [OR=2.1 (95% CI 1.6-7.1)] and age over 35 years [OR=1.4 (95% CI 1.2-6.6)]. Conclusions : From our study, the risk factors for placenta praevia are a history of retained placenta, previous caesarean section, previous abortion, grand multiparity and maternal age over 35 years. (East African Medical Journal: 2002 79(10): 536-538)