Value of endometrial thickness change after human chorionic gonadotrophin administration in predicting pregnancy outcome following fresh transfer in vitro fertilization cycles.

PURPOSE: To study whether the change of endometrial thickness (EMT) between the day of human chorionic gonadotrophin (hCG) administration and the day of embryo transfer has any impact on pregnancy outcome in fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles.

METHODS

This single-center retrospective cohort study included 2620 patients undergoing their first consecutive autologous IVF/ICSI cycles from January 2003 to December 2012. Patients were categorized into three groups based on the percentage change of post-hCG EMT: > 10% decrease, ± 10% plateau and > 10% increase. The primary outcome was live birth rate.

RESULTS

Live birth rates were similar in the EMT decrease, plateau and increase groups (27.4% [174/635], 29.7% [300/1010] and 27.6% [269/975]; P = 0.649). Compared with the plateau group, both EMT decrease (crude odds ratio [cOR] 0.89, 95% confidence interval [CI] 0.72-1.11) and increase (cOR 0.90, 95% CI 0.74-1.10) on the day of transfer did not affect the likelihood of live birth. The non-significant association was maintained after controlling for major confounding factors, with the adjusted OR being 0.92 (95% CI 0.73-1.16) and 0.92 (95% CI 0.75-1.13) for the decrease and increase groups, respectively.

CONCLUSION

EMT change after hCG administration did not provide significant prognostic information for pregnancy outcome in fresh IVF/ICSI cycles. This finding should offer reassuring information for patients with decreased EMT on the day of embryo transfer while questioning the necessity of EMT re-measurement prior to transfer as a routine practice.