Overexpression of estrogen and progesterone receptors as indicator of endometrial receptivity disorder in women with early miscarriage

Background ― The endometrial factor is important in miscarriage (MC) pathogenesis. Objective. To perform a morphofunctional evaluation of endometrium in the patients with uncertain MC cause in anamnesis. Material and methods ― We examined 48 women 23-40 yo [30 (27, 35)]: the main group consisted of 33 patients with early MC in their medical history, while the control group included 15 healthy fertile women. All women had an ovulatory menstrual cycle, normal levels of gonadotropic and thyroid hormones, prolactin, and androgens. Ultrasound and hormonal examinations, along with morphological investigation of endometrial biopsies were performed. Data presented as median with lower and upper quartiles – Me (LQ, UQ). Results ― In 64% (n=21) of women in the main group, we detected inferior secretory phase of their endometrial cycle, focal fibrosis of endometrial stroma; synchronous overexpression of estrogen (ER) and progesterone (PR) receptors in endometrial glands and stroma. ER in the glands was 240 (160, 280) vs. 130 (80, 210) in the stroma, while PR values were 270 (210, 290) in the glands vs. 270 (240, 280) in the stroma: differences from the control group were significant (p<0.01). Remaining women in the main group (36%, n=12) and all women in the control group had full secretory transformation of the endometrium and normal expression of ER and PR. The levels of estradiol and PR in the blood of women with early MC in anamnesis, with different variants of ER and PR expression in the endometrium, did not differ significantly from the control group and corresponded to the reference values. Conclusion ― Nearly two-thirds of women with early miscarriage in anamnesis exhibited overexpression of ER and PR in the endometrium, which may be one of the indicators of its decreased receptivity status