Endometrial estrogen and progesterone receptor and pinopode expression in stimulated cycles of oocyte donors

Abstract Objective: To study the effect of controlled ovarian hyperstimulation and the ovarian response on several features of endometrial morphology simultaneously. Design: Prospective controlled study. Setting: Academic infertility center. Patient(s): Twenty-five oocyte donors undergoing COH and 10 ovulatory controls. Intervention(s): Endometrial biopsies during the luteal phase and measurement of serum E 2 and progesterone levels on days 12, 13, and 18–20. Main Outcome Measure(s): Endometrial morphology as judged by histologic dating, pinopode expression, and estrogen and progesterone receptor content. Result(s): Controlled ovarian hyperstimulation caused the early expression of endometrial features as judged by histologic dating criteria, estrogen and progesterone receptor expression, and the timing of pinopode expression in many of the subjects. A significant correlation within subjects with regard to their particular result on any one measure (e.g., histologic examination) and the others (e.g., estrogen and progesterone receptors, pinopodes) was observed. Those with higher levels of progesterone the day after hCG administration exhibited the most prematurity of morphologic features. Conclusion(s): Many controlled ovarian hyperstimulation cycles are associated with synchronous early expression of the expected pattern of histologic features, estrogen and progesterone receptors, and pinopodes. The most predictive feature of this premature expression was the level of progesterone the day after hCG administration.