Younger Women with Ovulation Disorders and Unexplained Infertility Predict a Higher Success Rate in Superovulation (SO) Intrauterine Insemination (IUI)

Introduction: Superovulation-intrauterine insemination (SO-JUT) is the most common assisted reproductive technique (ART) in the world, with good evidence of efficacy and cost-effectiveness. However, parameters affecting its success have not been consistently reported. So in this study, we aim at determining the parameters influencing the success rate of SO-JUT. Materials and Methods: We conducted a retrospective cohort study of 797 SO-JUT cycles from 606 patients, performed between 2007 and 2009 in a single centre. These women received clomiphene citrate (CC), recombinant FSH (rFSH) or both. Results: There were 127 clinical pregnancies with a pregnancy rate (PR) of 15.9% (127/797) per treatment cycle. Factors associated with higher PR included maternal age <38 (P = 0.02), subfertility diagnoses of ovulatory disorders, unexplained infertility, sexual dysfunction and unilateral tubal obstruction (P = 0.02), an endometrial thickness >= 8 mm (P = 0.03), total number motile spermatozoa (TNMS) of >= 1 million (P = 0.03), and spermatozoa normal forms (NF) >= 4% (P <0.01) on bivariate analysis. When CC is used, the endometrial thickness is more likely to be suboptimal (<8 mm). All the above parameters remained significant except the subfertility diagnoses on multivariate analysis. Conclusion: Patients' selection with women <38 years old and preferably with ovulation disorders and unexplained infertility is associated with the highest PR in SO-JUT. Cycle parameters such as the use of rFSH alone, with the avoidance of CC, TNMS >= 1 million and NF >= 4% is likely to result in the best outcomes and reduce the high order multiple pregnancy risk.