Comparison of daily and alternate day recombinant follicle-stimulating hormone stimulation protocols for intrauterine insemination.

OBJECTIVE To determine the efficacy of daily versus alternate-day stimulation for patients undergoing intrauterine insemination (IUI). DESIGN Retrospective comparative study. SETTING University tertiary care center for infertility. PATIENT(S) Women with anovulatory or unexplained infertility for over 12 months who had not responded to or not conceived with clomiphene citrate treatment. INTERVENTION(S) Ovarian stimulation with recombinant follicle-stimulating hormone (FSH; follitropin-beta) given either daily or on alternate days before IUI. MAIN OUTCOME MEASURE(S) Clinical pregnancy at ultrasound 4 weeks after IUI. Secondary outcome measures were duration of stimulation, total gonadotropin dose, ovarian response, and multiple pregnancy rate. RESULT(S) Of the 212 women who underwent a first cycle of gonadotropin stimulation, 28 had daily injections and 117 had alternate-day injections of follitropin-beta only for IUI. Female age, antral follicle count, and day-3 serum FSH were comparable. The median duration of stimulation (8 days vs. 8 days) and the median number of follicles over 14 mm (3.5 vs. 3.0) were similar in both groups. However, the total recominbinant FSH dose (825 vs. 625 IU) and endometrial thickness (10.1 vs. 9.3 mm) were greater in the daily injection group. The clinical pregnancy rate per cycle was 42% (12 out of 28) in the daily injection group and 19% (22 out of 117) in the alternate-day group. CONCLUSION(S) Daily recombinant FSH stimulation for IUI seems to be associated with a higher clinical pregnancy rate than alternate-day FSH stimulation. Prospective randomized trials would be needed to determine whether this is indeed the case.