To investigate the effect of Cangfu Daotan pill on pregnancy outcome of polycystic ovary syndrome (PCOS).Methods:A total of 112 patients with PCOS admitted by Shenzhen Traditional Chinese Medicine Hospital from January 2018 to January 2019 were divided into control group (n=56) and observation group (n=56).The control group was treated with routine western medicine and the observation group was treated with Cangfu Daotan pill,both for 3 months.The changes of sex hormone,uterine artery flow rate,endometrial thickness,ovarian volume and clinical symptom scores were observed before and after treatment,and the pregnancy outcome was evaluated.Results:1)After treatment,follicle stimulating hormone (FSH),total testosterone (T),luteinizing hormone (LH) and LH/FSH decreased in the two groups compared with before treatment,but there was no significant difference between the two groups (P>0.05).There was no significant difference in prolactin (PRL) and estradiol (E2) before and after treatment.2)After treatment,the resistance index (RI),pulsatility index (PI),the number of follicles and the volume of bilateral ovaries in the two groups decreased compared with before treatment,the systolic peak velocity,mean flow velocity,diameter of main follicles and endometrial thickness increased(P<0.05) and the observation group were significantly higher than those in the control group (P<0.05).3)The rate of endometrial type A,pregnancy rate,clinical pregnancy rate and improvement of clinical symptoms in the observation group were significantly higher than those in the control group (P<0.05).Conclusion:Cangfu Daotan pill can improve the pregnancy outcome and clinical symptoms of polycystic ovary.