Increased endometrial thickness on the day of human chorionic gonadotropin injection does not adversely affect pregnancy or implantation rates following in vitro fertilization-embryo transfer.

OBJECTIVES: To investigate the controversy whether an increased endometrial thickness has an effect on pregnancy, implantation, or abortion rates in in vitro fertilization-embryo transfer (IVF-ET) cycles.

DESIGN: Retrospective analysis.

SETTING: A university-based IVF center.

PATIENT(S): Five hundred seventy women under the age of 40.

INTERVENTION(S): Measurements of endometrial thickness on day of human chorionic gonadotropin (hCG) administration. Cycles were compared by endometrial thickness of 14 mm in 60 women.

MAIN OUTCOME MEASURE(S): Implantation, pregnancy, and abortion rates.

RESULT(S): Implantation, pregnancy, and abortion rates were similar in each group. In cycles where the endometrial thickness was 14 mm.

CONCLUSION(S): No adverse effects of a thickened endometrium were demonstrated on implantation, pregnancy, or abortion rates in the first IVF-ET cycle. These findings fail to corroborate with those of Weissman et al. and support those of Yakin et al.