comparison of treatment outcomes of infertile women by clomiphene citrate and letrozole with gonadotropins underwent intrauterine insemination

this study was designed to compare the effect of clomiphene and letrozole in ovulatory stimulation in infertile women under intrauterine insemination who referred to mahdiyeh infertility clinic during 2008-2009. 106 infertile women were randomly divided into two equal groups. patients were treated with 5 mg of letrozole daily (in letrozole group) or 100 mg of clomiphene citrate daily (in clomiphene group) for five days starting on day 3 of their menses. dose and time of fsh was similar in the two groups. number of follicles, endometrial thickness, pregnancy rate and prevalence of complications were compared in the two groups. mean (±sd) of age in letrozole and clomiphene groups was 26.3 ±3.9 and 25.2 ±4.9 respectively (p=0.186). average number of follicles was 2.5 ± 1.65 in letrozole group and 2.36 ± 1.4 in clomiphene group (p=0.764). β-hcg was positive in 11 (20.8%) in letrozole and 12 (22.6%) in clomiphene groups (p=0.814). pregnancy rate was 20.8% and 22.6% in letrozole and clomiphene group respectively (p=0.814). there was no difference in rate of abortion between groups. endometrial thickness (et) at the time of hcg administration in the letrozole (6.8 ±1.5 mm) and in clomiphene (6.6 ±1.2 mm) (p=0.615). but et>7.4 mm was found in 2 cased (3.8%) in clomiphene group and 12 cases (%22.8) in letrozole groups (p=0.01). it appears that letrozole and clomiphene have similar outcome infertile women under intrauterine insemination and these drugs are good alternative for each others.