Clinical analysis on the promoting effects of two different doses of letrozole on ovulation in infertile patients with polycystic ovary syndrome

Objective:To compare the promoting effects of two different doses of letrozole on ovulation in infertile patients with polycystic ovary syndrome(PCOS) and the impacts on reproductive hormones.Methods:A total of 151 infertile patients with PCOS who planned to receive ovulation treatment were randomly divided into two groups: 69 patients in group A were treated with oral administration of 2.5 mg letrozole every day from the third day to the seventh day during menstrual cycle,while 82 patients in group B were treated with oral administration of 5.0 mg letrozole every day.Ultrasonography was performed to monitor follicular development,the venous blood specimens were obtained on the eighth day during menstrual cycle and the day of human chorionic gonadotropin(HCG) injection to detect the levels of luteinizing hormone(LH),estradiol,and testosterone;the number of dominant follicles,the number of mature follicles,the ovulation rate,the pregnancy rate,the thickness of endometrium,the multiple pregnancy rate,the incidence of ovarian hyperstimulation syndrome(OHSS),and the changes of reproductive hormones were observed.Results:The number of dominant follicles and the number of mature follicles on the day of HCG injection in group B were significantly higher than those in group A,the follicular mature time in group B was less than that in group A,there was statistically significant difference between the two groups(P0.05).The cycle pregnancy rate in group B was statistically significantly higher than that in group A(P0.01).There was no statistically significant difference in the ovulation rate and the thickness of endometrium on the day of HCG injection between the two groups(P0.05).No multiple pregnancy and OHSS occurred in the two groups.Conclusion:The number of dominant follicles,the number of mature follicles,and the cycle pregnancy rate in group B were statistically significantly higher than those in group A.