Doctors' Preferences for Controlled Ovarian Stimulation Protocols in Intrauterine Insemination.

Intrauterine insemination (IUI) is an important treatment for infertility. IUI combined with controlled ovarian stimulation (COS) is widely used because of the higher pregnancy rates compared to IUI cycles without COS.We retrospectively analyzed a single center data from 458 patients underwent the first IUI cycle and had only 1 mature follicle from May 2009 to January 20144. 48 cycles were performed with Clomiphene citrate/Letrozole (CC/LE), 244 cycles with gonadotropins (Gn), 71 cycles with CC/LE+Gn, and 95 cycles in NC group.Results showed that doctors preferred Gn protocol (53.3%) (p<0.05). Older patients were more likely to be allocated to CC/LE or NC group. 98.95% patients in NC group had regular menstruation cycle, with only 49.3% in CC/LE+Gn group (p<0.05). Estradiol (E2) level was much higher in COS groups than in NC group (p<0.05, for one mature follicle patients), and no significant differences were found within the COS groups. Duration of reaching follicles maturation was the shortest in Gn group and the longest in NC group, and NC group has the smallest follicular diameter (p<0.05).No significances were found regarding the IUI outcomes. To sum up, doctors prefer COS for IUI. Patients' age, menstruation cycle, infertile etiology and ovary function were the main factors affecting doctors' selection of COS protocols.