OBJECTIVETo study the effect and potential mechanism of Modified Cangfu Daotan Decoction (MCDD) on endometrial receptivity in infertility patients with polycystic ovarian syndrome (PCOS).

METHODSTotally 298 women having normal ovulation who underwent artificial insemination were recruited as the control group, and they received no drug therapy. Another 355 infertility patients with PCOS who received ovarian stimulation therapy were recruited as the treatment group. Then they were further assigned to the treatment group I (195 cases) and the treatment group II (160 cases) according to random digit table. Patients in the treatment group I received clomiphene (CC) + human menopause gonadotropin (HMG) +human chorionic gonadotropin (HCG), while those in the treatment group II received CC + HMG + HCG and additionally took modified MCDD. The therapeutic course for all was three menstrual cycles. The pregnancy ratio, the endometrial thickness, and spiral artery pulsatility index (PI), resistance index (RI), and homeostasis model assessment-insulin resistance (HOMA-IR) were measured. Furthermore, the uncoupling protein 2 (UCP2) level was tested by Western blot.

RESULTSCompared with the control group, the endometrial thickness decreased and PI and RI increased in the treatment group I (all P < 0.05). Compared with the treatment group I , the endometrial thickness increased and PI and RI decreased in the treatment group II (all P < 0.05). Compared with before treatment, HOMA-IR levels were significantly decreased in the treatment group II after treatment (P < 0.05). Compared with the control group before treatment, the HOMA-IR level increased in the treatment group I and the treatment group II before treatment (P < 0.05). Compared with the control group after treatment, the HOMA-IR level increased in the treatment group I (P < 0.05). But there was no statistical difference in the post-treatment HOMA-IR level between the control group and the treatment group II (P < 0.05). Compared with the control group, the post-treatment UCP2 level was increased in the treatment group II (P < 0.05). After one year follow-up, the pregnancy rate was 16.1% (48/298) in the control group, 23.1% (37/160) in the treatment group I, and 33.8% (66/195) in the treatment group II. Compared with the control group, the pregnancy rate was significantly increased in the treatment group II (P < 0.05).

CONCLUSIONMCDD was found to be capable of increasing the pregnancy rate of infertility patients with PCOS, which might be associated with improving endometrial blood flow and insulin resistance, increasing the UCP2 expression, and finally improving the endometrial receptivity.