Background & Aims : Lack of ovulation is usually the reason for fertility problems in women and polycystic ovary syndrome (PCOS) is a common disorder in women of reproductive age that is associated with infertility and chronic lack of ovulation. Recent studies proved aromatase inhibitor letrozole as an ovulation induction agent. Since letrozole is a drug used to stimulate ovulation in women with PCOS, we aimed to compare the effects of letrozole ovulation induction with clomiphene citrate success in patients with polycystic ovary syndrome.

  Materials & Methods : This controlled clinical trial was carried out by the year 2011 in Kosar infertility center in Urmia. 220 patients with PCOS at the age of 20-35 submitted and were randomly divided into: A. clomiphene citrate(cc) and B. letrozole groups. Each group contained 110 patients, that were respectively treated by 100 mg of clomiphene or 5 mg of letrozole. After then, all the patients were treated with gonadotropin and HCG and underwent common IUI infertility treating method. The results were analyzed by SPSS software.

  Results : In this study, the mean age of patients was not statistically different in two groups.(26.29±3.9 Vs. 27.28±4.6). Although both endometrial thickness and follicles counts statistically differed between clomiphene and letrozole (Respectively 2.28 ±1.13 Vs.1.83 ±0.88 for follicles counts and 7.3± 1.2 Vs. 8.7 ±1.18 for endometrial thickness, both P values=0.001) the difference between rates of pregnancies was not statistically significant between two groups (Respectively 18/2% Vs. 27/3% , P=0.1).

  Conclusion: The occurrence of pregnancy in patients who received letrozole was higher but not significant and at the same time the probability of multiple pregnancies was lower than clomiphene receivers. Therefore, in infertile patients PCOS letrozole can be offered as an effective first-line alternate option for Clomiphene citrate.  

  SOURCE: URMIA MED J 2013: 24(7): 549 ISSN: 1027-3727