Letrozole + Ziwu Liuzhu Transcutaneous Electrical Acupoint Stimulation Improves Ovulation-Induced Pregnancy Rate in Obese Women with Polycystic Ovary Syndrome: A Prospective Cohort Study

Abstract

Objective: This study investigated the effect of letrozole with/without meridian-infusion percutaneous electrical stimulation on the rates of ovulation-induced pregnancy in patients with obese polycystic ovary syndrome (obPCOS).

Materials and methods: Patients with obPCOS, ages 20-40, each with a body mass index (BMI) ≥24 kg/m², and/or waist circumference ≥80 cm, and at least 1 side tubal patency were enrolled at the Guangdong Women and Children Hospital, Guangzhou, China. They were divided into 2 groups: ZLT [Ziwu Liuzhu + transcutaneous electrical acupoint stimulation] and control. Baseline conditions and pregnancy status were collected for all patients. Multivariate Cox regression analysis and sensitivity analysis of propensity score matching (PSM) were performed for the groups after multiple interpolations.

Results: From July 2021 to September 2022, 345 patients with obPCOS were recruited: 53 cases/69 cycles in the ZLT group and 292 cases/396 cycles in the control group. The 2 sets of baselines were flush. The anovulatory cycle rates were: ZLT, 2.89% (2/69); and control, 1.77% (7/396); P > 0.05. Multifollicle growth-cycle rates were: ZLT, 0% (0/69); and control, 0.76% (3/396); P > 0.05. Multivariate COX regression analysis showed adjusted hazard ratio (aHR) 95% confidence interval (CI): 2.11 (1.19, 3.73); P = 0.011. Multivariate Cox regression analysis with multiple imputation showed aHR 95% CI: 2.11 (1.19, 3.73); P = 0.013. In the overweight group (24-28 kg/m²), the pregnancy rate of the control and ZLT groups were 20.2% and 32.3%, respectively, aHR 95% CI: 1.76 (0.87,3.55); P = 0.113. In the obese cohort (≥ 28 kg/m²), the control and ZLT groups, pregnancy rates were 10.7% and 27.3%, respectively, aHR 95% CI: 3.46 (1.21, 9.92); P = 0.021; (P_{for interaction} = 0.369). The caliper value was set as 0.2 for BMI and antral-follicle count, and PSM was performed at 1:1, aHR 95%CI: 2.45 (1.01, 5.96); P = 0.048.

Conclusions: Letrazole + ZLT had a positive effect on ovulation-induced pregnancy rates in patients with obPCOS.

Keywords: electrical stimulation of percutaneous acupuncture points; letrozole; meridian flow injection; obese polycystic ovary syndrome; ovulation pregnancy rate.

FIG. 1.

Cumulative pregnancy curves for patients with polycystic ovary syndrome in the ZLT [Ziwu Liuzhu + transcutaneous electrical acupoint stimulation] and control groups.