A comparison of effects and pregnancy outcome of letrozole versus clomiphere citrate for ovulation induction

Objective To search for a new drug for ovulation induction through a comparison of the effects and pregnancy outcome of letrozole(LE) versus clomiphere citrate(CC) for ovulation induction.Methods Twenty-one patients were treated with LE.Thirty-one patients were treated with CC.The indices of their follicle growth,endometrial development were observed.Meanwhile,the pregnancy rates were recorded as well as the case of miscarriage,ectopic pregnancy and ovarian hyperstimulation syndrome(OHSS).Results Compared with the CC group,letrozole was associated with statistically significantly fewer follicles≥14mm,endometrial thickenss was thicker on the day of HCG.Two groups had no one patient with OHSS.The pregnancy rate and ongoing pregnancy rate were higher in the LE group,but a marked difference was not found between the two groups.Conclusion Letrozole results in stimulation of ovarian folliculogenesis and the pregnancy rate are similar to those with CC.LE can avoid the unfavorable effecs on the ovaries and endometrium.