Systematic Review of Postfertilization Effects and Potential for Embryo Formation and Loss during the Use of Intrauterine Devices.

A systematic review was carried out examining the English-language literature in the MEDLINE, EMBASE, and Ovid databases for evidence of embryo formation and loss during IUD use. In all, 1,073 studies were identified and 138 were read. There are no randomized trials and evidence ranges in quality, but evidence for the embryo formation and loss in 4.5 percent of IUD users exists in good-quality research. Further research is needed to compare embryo loss in IUD users to loss in controls.