Abstract: Objective To investigate the effect of intrauterine infusion of human chorionic gonadotrophin(hCG) on endometrial receptivity, estrogen and progesterone and their receptors in patients with polycystic ovary syndrome(PCOS). Methods The control group(n=23) consisted of healthy females, the study group consisted of PCOS patients. The study group 1(n=25) was given letrozole, and the study group 2(n=20) was given letrozole. Two days before ovulation and on the ovulation day, hCG 500 IU/mL was intraperitoneally administered. Endometrium was taken from D6 to D8 after ovulation in each group. Immuno-histochemical staining was used to detect the expression of estrogen receptor(ER) and progesterone receptor(PR). Scanning electron microscopy(SEM) was used to observe endometrial pinopode. The serum estrogen(E2) and progesterone(P) were examined by through chemi- luminescence on the endometrial day. Sixteen days after ovulation, the pregnancy rate of each group was calculated. Results The expression rate of the mature stage pinopode in the study group 1 was lower than that in the control group. The expression rate of the mature stage pinopode in the study group 1 was higher than that of study group 1(P＜0.05). The P level of the implantation window and the positive expression rate of PR in the study group 1 was lower than that in the control group. The P level of the implantation window and the positive expression rate of PR in the study group 1 was higher than that in the study group 1(P＜0.05).The pregnancy rate of study group 1 was lower than that of the control group, and the pregnancy rate of study group 2 was higher than that of study group 1(P＜0.05). Conclusions PCOS patients are stunted during the implantaqtion window. Intrauterine perfusion of hCG may increase the number of mature pinopode and improve endometrial receptivity. This is potentially related to increased P level and PR expression.

Key words: polycystic ovarian syndrome, intrauterine infusion, human chorionic gonadotrophin(hCG), pinopode