The Association between Oral Contraceptive Pills and Subtypes of Ovarian Cancer: A Sys- tematic Review and Meta-Analysis

Introduction: Limited studies have been conducted on the effect of oral contraceptive pills on the subgroupsof ovarian cancer, so we decided that conduct a systematic review and meta-analysis to investigate the effectof preventive pills on ovarian cancer subgroups. Methods: Scopus, PubMed, Web of Science and EMBASE were searched to identify studies on the associationbetween OCPs and subtypes of ovarian cancer from January 1, 2000, through February 5, 2023. The pooledrelative risk (RR) and odds ratio (OR) were used to measure this association. Results: A total of 48 studies were included. In the association between ever-use compared with never-use ofOCPs and ovarian cancer risk, the pooled RR in cohort studies was 0.69 [95% CI: 0.61, 0.78], and the pooledOR of the case-control studies was 0.64 [95% CI: 0.59, 0.69]. For the association between OCPs and subtypesof ovarian cancer, there is a significant inverse association between OCPs and serous 0.72 [95% CI: 0.23, 0.82]and endometrioid 0.74 [95% CI: 0.64, 0.86], but no association between OCPs and clear cell 0.84 [95% CI:0.60, 1.16] and mucinous 0.80 [95% CI: 0.63, 1.01]. Conclusion: This study shows a statistically significant inverse association between ever-use compared tonever-use of OCPs and ovarian cancer risk. Also shows a statistically significant inverse association betweenserous and endometrioid cancer and OCPs, but no association between OCPs and clear cell and mucinous.