Abstract: Objective: To assess the effects of male factors on the clinical pregnancy rate of intrauterine insemination（IUI）. Methods： The data of 472 IUI cycles from January 2012 to April 2013 in our center were retrospectively analyzed. These cycles were divided into three groups according to male age（＜30，30～35，≥35 years），four groups according to the percentage of normal morphological spermatozoa（normal：≥15%；mild，moderate and severe abnormal：10%-15%，5%-10%，≤4%）, or five groups according to the processed total motile sperm count（PTMS）（＜2×106，（2-5）×106，（5-10）×106，（10-20）×106，≥20×106）. Then the clinical pregnancy rates were compared. Results：A total of 80 clinical pregnancies were obtained，for a pregnancy rate per cycle of 16.95% and accumulative rate 33.47%. The clinical pregnancy rate in the ≥35 years old group was 10.4%，in severe abnormal group was 8.4%. These rates were significantly lower than those of other groups（P＜0.05）. Conclusions：Male factors such as age, the percentage of normal morphological spermatozoa, and PTMS should be considered during IUI therapy. Those couples with male age ≥35 years, severe abnormal spermatozoa, or PTMS ＜2×106, should be advised to treat with IVF-ET or ICSI-ET.

Key words: Infertility, male, Insemination, artificial, Pregnancy rate, Treatment outcome, Paternal age, Spermatozoa