A PubMed search was conducted using the following search string: ((((((“Obstetrical & gynecological survey”[Journal] OR “Obstetrics and gynecology”[Journal]) OR “American journal of obstetrics and gynecology”[Journal]) OR “Gynecologic oncology”[Journal]) OR “Human reproduction update”[Journal]) OR “BJOG : an international journal of obstetrics and gynaecology”[Journal]) AND (“2007/01/01”[PDAT] : “2015/12/31”[PDAT]) AND “humans”[MeSH Terms]) AND (((meta-analysis[Title/Abstract] OR meta-analysis[Publication Type]) OR systematic review[Title/Abstract]) AND (“2007/01/01”[PDAT] : “2015/12/31”[PDAT]) AND “humans”[MeSH Terms]) AND ((“2012/01/01”[PDAT] : “2015/12/31”[PDAT]) AND “humans”[MeSH Terms]). Journals were selected based on the highest 2014 h5-index of Google Scholar. This search strategy was adapted from a previously published approach that is sensitive to identifying systematic reviews and meta-analyses \cite{15619601}. Searches were conducted on May 18 and May 26, 2015.