To observe the effect of acupuncture on endometrium and pregnancy outcomes in patients with polycystic ovary syndrome (PCOS) infertility undergoing in vitro fertilization-embryo transfer (IVF-ET).Eighty-three patients were randomly assigned to observation group (40 cases) and control group (43 cases) according to the random numbers generated by SPSS software. The patients of the two groups received GnRH agonist long protocol as a routine treatment. In the observation group, acupuncture was given at two acupoint groups for 30 min once every other day. Group 1 included Guanyuan (CV 4), Qihai (CV 6), Zhongji (CV 3), bilateral acupoints Zigong (EX-CA1). Group 2 included Mingmen (GV 4), Yaoyangguan (GV 3), bilateral Shenshu (BL 23) and Ciliao (BL 32). The two groups of acupoints were used alternately. The whole needling process was performed at the time of ovulation induction until the transplantation day and consisted of 3 courses, while the control group did not receive acupuncture interventions. The Gn dosage and Gn stimulation time, endometrial thickness and type (A, B, and C), serum oestradiol (E2) and progesterone (P) levels on the day of injection of human chorionic gonadotropin (hCG), clinical pregnancy rate, as well as live birth rate were observed. Adverse reactions were also be recorded. All patients were followed up for the pregnant rate 14 days after IVF-ET and live birth rate after pregnancy. All adverse reactions (AEs) of acupuncture were recorded during the trial.The Gn dosage and Gn stimulation time in the observation group were lower in the observation group than in the control group (P<0.01). The proportion of type A endometrium in the observation group were higher than that in the control group (P<0.05). The serum E2 and P levels on the day of hCG injection was lower and the clinical pregnancy rate was higher in the observation group compared to those in the control group (P<0.05). There was no serious AEs during this trial.Acupuncture can improve the proportion of type A endometrium, regulate the levels of serum E2 and P on the day of hCG injection, and improve the pregnancy rate in patients with PCOS infertility undergoing IVF-ET.© 2022. The Chinese Journal of Integrated Traditional and Western Medicine Press and Springer-Verlag GmbH Germany, part of Springer Nature.