The Effect of Luteal Phase Support on Pregnancy Rates of the Stimulated Intrauterine Insemination Cycles in Couples with Unexplained Infertility

Background: To assess the efficacy of luteal phase support (LPS) with vaginal progesterone (P) on pregnancy rates of the stimulated intrauterine insemination (IUI) cycles in couples with unexplained infertility (UEI). Materials and Methods: This was a single-center, prospective, randomized, blinded control trial undertaken at a tertiary care university fertility center between October 2007 and December 2008. A total of 200 couples with UEI underwent 511 consecutive stimulated IUI cycles. Clomiphene citrate (Cc) and human menopausal gonadotropin (hMG) were used for ovulation induction. After IUI, patients were randomized into two groups. The study group (n=98) received intra-vaginal P (Cyclogest) for LPS. The patients randomized into the control group (n=102) received no drug for LPS. The main outcome was the comparison of clinical pregnancy rate (PR) and live birth rate (BR) per cycle and patient between the control and study groups. Results: There were no differences in demographic characteristics between the groups. PR per patient and cycle were similar in the study group (30.6% and 11.5%, respectively) and in the control group [25.5% and 10.03%, respectively] (p>0.05). There were no statistically significant increases in BR per patient and cycle between the study group (19.4% and 7.5%, respectively) and the control group [14.7% and 5.7%, respectively] (p>0.05). Conclusion: Administration of vaginal P (Cyclogest) for LPS does not improve the reproductive outcome of stimulated IUI cycles (Registeration Number: IRCT1389 01283737N1).