Abstract: Objective：To investigate the association between follicle size on human chorionic gonadotropin (hCG) day and clinical pregnancy rate in cycles with clomiphene citrate. Methods：212 infertile couples who accepted artificial insemination with donor semen treatment cycles were evaluated retrospectively in this study. They were divided into four groups according to the diameter of leading follicle on the day of hCG ｉｎｊｅｃｔｉｏｎ： ｇｒｏｕｐ Ａ（１８-１９．５ ｍｍ）， ｇｒｏｕｐ Ｂ（２０-２１．５ ｍｍ）， ｇｒｏｕｐ Ｃ（２２-２３．５ ｍｍ） ａｎｄ ｇｒｏｕｐ Ｄ（ａｂｏｖｅ ２４ ｍｍ）． Ｔｈｅ ｐｒｅｇｎａｎｃｙ ｏｕｔｃｏｍｅｓ ｗｅｒｅ ｃｏｍｐａｒｅｄ． Ｒｅｓｕｌｔｓ：Ｔｈｅ ｐｒｅｇｎａｎｃｙ ｒａｔｅｓ ｏｆ ｆｏｕｒ ｇｒｏｕｐｓ ｗｅｒｅ ２４．３９％， １４．２９％， １８．１８％ ａｎｄ ７．１４％． Ｔｈｅｒｅ ｗａｓ ｎｏｔ ｓｉｇｎｉｆｉｃａｎｔ ｄｉｆｆｅｒｅｎｃｅ ａｍｏｎｇ ｔｈｅ ｆｏｕｒ ｇｒｏｕｐｓ（Ｐ＞０．０５）． Ｃonclusions：There is not association between pregnancy rate of AID in cycles with clomiphene citrate and follicle size on hCG day according to our present study.

Key words: Reproductive techniques, assisted, Insemination, artificial, Clomiphene, Ovarian follicle, Pregnancy rate