Clinical and Experimental Obstetrics & Gynecology (CEOG) is published by IMR Press from Volume 47 Issue 1 (2020). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on imrpress.com as a courtesy and upon agreement with S.O.G.
Comparable implantation rates with fresh vs frozen embryo transfer suggests that controlled ovarian hyperstimulation has an adverse effect on conception outcome
Purpose: A retrospective comparison of fresh vs frozen embryo pregnancy rates. Methods: All frozen embryos transferred used in the analysis including deselected embryos from the oocyte retrieval cycle, and twice-frozen embryos. Results: Pregnancy and implantation rates following fresh or frozen embryo transfers were similar. Conclusion: The similar outcomes despite the obvious disadvantages for the frozen-thawed embryo suggests that some other factor reduces the chance of embryo implantation on oocyte-retrieval cycles. An adverse affect of controlled ovarian hyperstimulation on the uterine environment is a strong possibility.