Predictive factors influencing pregnancy rates after intrauterine insemination

Background: So far, many studies investigated factors that affect pregnancy rates after intrauterine insemination (IUI). Various investigators have not agreed on the nature and ranking of these criteria.
Objective: The aim of this study was to assess the predictive factors for pregnancy rate after controlled ovarian hyperstimulation (COH)/ IUI.
Materials and Methods: Retrospective study of all patients undergoing IUI at Zeynep Kamil Gynecologic and Pediatric Training and Research Hospital from January 2006 to December 2009. In total 980 IUI cycles in 569 couples were analyzed. All women in the study underwent ovarian stimulation using gonadotropin and IUI was performed 36 h after triggering ovulation. The primary outcome measure was clinical pregnancy rates. Predictive factors evaluated were female age, body mass index (BMI), duration of infertility, type of infertility, follicle stimulating hormone (FSH) level and estradiol (E2) on third day of the cycle, number of preovulatory follicles, endometrial thichness, total motil sperm (TMS) count, and ratio of progressive motile sperm.
Results: The overall clinical pregnancy rate was 4.7%. Among the predictive factors after multivariate logistic regression analysis level of BMI (<25 kg/m²), number of preovulatory follicles (≥2), level of FSH (<9.4 IU/L), level of E2 (<80 pg/ml) and the ratio of progressive motile sperm (>50%) significantly influenced the clinical pregnancy rate.
Conclusion: Level of BMI, FSH, estradiol, number of preovulatory follicles and the ratio of progressive motile sperm may determine IUI procedure as optimum treatment model.

Keywords
Intrauterine insemination, Pregnancy rate, Predictive factor, Gonadotropin, Progressive motile spermatozoa