Background: There is a contradict results regarding the effect of previa on the preeclampsia. Therefore this study aimed to systematically review of relevant literatures and determine the association between placenta previa and pre-eclampsia in pregnant women.
Materials& methods: Electronic scientific databases including: Scopus, PubMed and Web of Science were searched to identify relevant published studies. Two independent authors studied the selected studies and extracted data. I² statistics was used to assess the variation across studies. The random effects model was used to assess pooled effect sizes. Data were analyzed through Stata software version 12.
Results: The results of present meta-analysis of nine studies indicated a significant relation between placenta previa and risk of preeclampsia. The odds of preeclampsia in placenta previa cases compared control groups was 0.55 (95% CI: 0.26, 0.85), and in studies with adjustment on confounder variables was 0.17(95% CI: 0.07, 0.27).
Conclusions: Our results showed that placenta previa is associated with decrease incidence of preeclampsia.