Superovulation with human menopausal gonadotropins is associated with endometrial gland-stroma dyssynchrony *

Objective To investigate the prevalence of endometrial inadequacy in endometrial biopsies from women undergoing superovulation with hMG and to correlate these findings with the hormonal milieu. Design Controlled, retrospective analysis. Setting University-based, tertiary referral, outpatient infertility clinic. Subjects Endometrial biopsies were performed during the late luteal phase in 89 women undergoing hMG superovulation combined with IUI. Results were compared with the initial biopsies obtained as part of their routine infertility evaluation. Main Outcome Measures Biopsies were dated by two different observers using standard dating criteria. Serum samples obtained during the midluteal phase were assayed in duplicate for E 2 and P levels using commercially available RIAs. Results Fifty-seven percent of the endometrial biopsies showed differences in the dating of the glandular epithelium that differed by >2days when compared with the stroma. In contrast, only 13% of endometrial biopsies obtained during a nonstimulated cycle showed gland-stroma dyssynchrony. When cycles associated with gland-stroma dyssynchrony were compared with cycles associated with coordinated development of the glands and stroma, no significant differences were observed in E 2 level on the day of hCG administration, midluteal serum P, midluteal E 2 level, or P:E 2 ratios. Conclusions This study demonstrates that when endometrial biopsies are obtained during the late luteal phase in patients undergoing ovarian hyperstimulation there is a significant dyssynchrony in the maturation of the glandular epithelium and the stroma. This may reflect the degree of responsiveness of an individual woman's endometrium rather than a result of the hormonal milieu.