The association between oral contraceptive pills and ovarian cancer risk: A systematic review and meta-analysis

Abstract

Introduction > Previous study results have been inconclusive, so this meta-analysis aims to evaluate the association between ovarian cancer and oral contraceptive pills (OCPs). Methods > PubMed, EMBASE, Scopus, and Web of Science were searched to identify studies on the association between OCPs and ovarian cancer from January 1, 2000 through February 5, 2023. The pooled relative risk (RR) and odds ratio (OR) were used to measure this relationship. Results > A total of 67 studies were included. In the association between ever-use compared with never-use of OCPs and ovarian cancer risk, the pooled RR in cohort studies was 0.69 95% CI: 0.61, 0.78. For the relationship between duration of OCPs use and ovarian cancer in the cohort studies, no association between duration of use1-12 months 0.92 95% CI: 0.82, 1.03 and duration of use 13-60 months 0.87 95% CI: 0.73, 1.04, but there is a statistically significant inverse relationship between duration of use 61-120 months 0.62 95% CI: 0.48, 0.81 and more than 120 months 0.51 95% CI: 0.32, 0.80 and ovarian cancer. For the relationship between OCPs and histological subtype of epithelial ovarian cancer in the cohort studies, the pooled RR for invasive was 0.70 95% CI: 0.56, 0.87, but no association between OCPs and borderline ovarian cancer 0.64 95% CI: 0.31, 1.31. Conclusion > Our analysis shows a statistically significant inverse relationship between ever-use compared to never-use of OCPs and ovarian cancer risk,and also between invasive cancer and OCPs. By increasing the duration of OCPs use, the risk of ovarian cancer decreased.