According to the studies CC is successful at inducing ovulation in 50%-75% of cases, but only 30-40% becomes pregnant. The difference has been attributed to a negative action of clomifen citrate(CC) in the form of prolonged antiestrogenic effects on endometrial receptivity. For avoiding of these negative effects, giving ethinyl estradiol in sufficient dosages may be effective. The purpose of this study is comparing pregnancy rates after IUI in women who use CC alone and those who use CC in combination with ethinyl estradiol