Objective To research the effects of Professor CAI Xiaosun’ s menstruation periodic treatment on hemodynamics of uterine artery and ovarian artery in infertility patients with polycystic ovary syndrome（ PCOS）. Methods Totally 25 infertility patients with PCOS were given modified Duonang Formula（ formula for PCOS） during the later period of menstruation or single phase of basal body temperature（ BBT） and modified Yushen Peiyuan Formula（ formula to supplement the kidney and origin） during the earlier period of menstruation or dual phase of BBT. Three months were one treatment course. The therapeutic effect was observed after one or two consecutive treatment courses. The follicular development was monitored before and after treatment. The resistance index（ RI） was calculated according to the peak systolic flow velocity（ Vmax） and diastolic velocity（ Vmin） of uterine artery and ovarian artery. Results There were 7 patients received one treatment course and 18 patients received two treatment courses and the total effective rate was 84. 00%. There were 19 patients with small follicles

5 patients with dominant follicles and 1 patient with mature follicle before treatment. There were 14 patients with small follicles

7 patients with dominant follicles and 4 patients with mature follicles after treatment. There was a significant difference between before and after treatment in the follicular development（ P < 0. 01）. The Vmax of uterine artery

Vmax of bilateral ovarian arteries and RI were significantly improved after treatment（ P < 0. 05 or P < 0. 01）. Conclusion Professor CAI Xiaosun’s menstruation periodic treatment can improve local microcirculation

increase blood supply to the uterus and ovaries

promote follicular development

ovulation

decidua growth and implantation and achieve better clinical efficacy.