Ever-use of the intra-uterine device and the risk of ovarian cancer
The association between the use of the intra-uterine device (IUD) and the risk of ovarian cancer is not well known. In this study, we sought to determine whether the use of an IUD is associated with a reduction in the risk of ovarian cancer. We searched Medline, EMBASE, Google Scholar, Scopus, ISI Web of Science and Cochrane database search, as well as PubMed (www.pubmed.gov) and RCT registry (www.clinicaltrials.gov) until the end of June 2019 to conduct a systematic review and meta-analysis comparing ever-use vs. never-use of an IUD and the risk of subsequent ovarian cancer. We obtained 431 records, of which 9 met inclusion criteria. A total of five case-control studies and four cohort studies were retrieved to establish the risk of ovarian cancer amongst ever-users of an IUD. Relative to the never-use of the IUD, ever-use conferred a lower risk of ovarian cancer with an estimated OR of 0.67 95% CI [0.60 - 0.74],