Previous Cesarean Section and the Risk of Preeclampsia: A Meta-analysis

Introduction: Preeclampsia is a common pregnancy complication with the multisystem variable disorder. Yet, the literature has not been systematically reviewed for the relationship between previous cesarean section and the risk of preeclampsia. Objective: This study aimed to identify the relationship between previous cesarean delivery and the risk of preeclampsia. Materials and Methods: This study was a systematic review and meta-analysis. PubMed, Scopus, ProQuest, and Web of Sciences were searched to identify eligible observational studies until May 25, 2019. The odds ratio (OR) and 95% confidence intervals (CI) were calculated as random effect estimates of association among studies. The quality of the included studies was examined based on the Newcastle-Ottawa scale. Results: This study included 7 eligible articles (2 studies with a case-control design, 4 with a cohort design, and 1 with a cross-sectional design). The meta-analysis results showed an increased risk of preeclampsia in the women with previous cesarean section compared to women without cesarean section (OR=1.28, 95% CI, 1.15%-1.41%, P=0.001), I2=37.2%. The quality of all studies except one study was high based on the Newcastle-Ottawa scale. The subgroup analysis was conducted based on the adjusted form of studies. The crude and adjusted studies were 1.29 (95% CI, 0.13%-2.46%, P=0.2) and 1.29 (95% CI, 1.22%-1.36%, P=0.001), respectively. Conclusion: These findings showed that previous cesarean section is a risk factor for preeclampsia. Therefore, education programs and interventions should be considered to reduce elective cesarean section on maternal requests.