The association between body mass index and preeclampsia: a meta-analysis

Background: Several observational studies have reported a positive association between elevated body mass index (BMI) and preeclampsia, but no meta-analysis has been conducted yet. This meta-analysis was conducted to estimate the overall association between overweight or obesity and preeclampsia.Methods: Major electronic databases, including PubMed, Web of Science, and Scopus were searched until August 2015. The reference lists of included studies were screened as well. Epidemiological studies addressing the association between BMI and preeclampsia were enrolled. The heterogeneity across studies was explored by Q-test and I-2 statistic. The possibility of publication bias was assessed using Begg's and Egger's tests. The results were reported using odds ratio (OR) estimate with its 95% confidence intervals (CI) using a random-effects model.Results: We identified a total of 1298 references and included 23 studies with 1 387 599 participants. Preeclampsia was associated with overweight (OR=1.73; 95% CI: 1.59, 1.87; 21 studies; I-2=62.3%) and obesity (OR=3.15; 95% CI: 2.96, 3.35; 22 studies; I-2=36.0%). There was no evidence of publication bias.Conclusions: There is sufficient evidence that excess body mass index is significantly associated with an increased risk of preeclampsia. Therefore, overweight and obesity can be considered as a predictor of preeclampsia.