The association between body mass index and the risk of endometriosis: A meta-analysis

Background: Many epidemiologic studies have been conducted to assess factors that were associated to endometriosis, but there is no consistency in results. Therefore, we conducted this meta-analysis to investigate the association between body mass index and the risk of endometriosis. Methods: In this meta-analysis, relevant studies that published in major international electronic bibliographic databases of PubMed, Scopus and Web of Science were systematically searched during November 2017. The Begg and Egger’s test was used to investigate publication bias in included studies. The Q-statistic and I 2 tests were carried out for measuring heterogeneity. The random-effects model was conducted to obtain pooled odds ratio. Results: Our results showed a direct association between underweight and endometriosis in woman (odds ratio = 1.41, 95% confidence interval = 1.16–1.66), so underweight woman had 41% higher chance for endometriosis. However, we did not find linear association between overweight and endometriosis (odds ratio = 0.95; 95% confidence interval: 0.72–1.18) and obesity and endometriosis (odds ratio = 0.88; 95% confidence interval: 0.54–1.21), respectively. Conclusions: Our results suggested that underweight was a risk factor for the endometriosis, while overweight and obesity were not protective factors for endometriosis.