2275 PREDICTIVE FACTORS OF INTRAUTERINE INSEMINATION SUCCESS: SPERM MORPHOLOGY ACCORDING TO THE NEW WORLD HEALTH ORGANIZATION LABORATORY MANUAL

INTRODUCTION AND OBJECTIVES: Despite intrauterine insemination (IUI) often has been used as a treatment for male factor infertility, seminal characteristics indicative of IUI success have not been defined clearly. Recently, the 5th World Health Organization (WHO) data described lower reference limits for the number of morphologically normal spermatozoa. The aim of our study was to assess the likelihood of IUI success as a function of the sperm morphology according to the new reference values defined by the recently published WHO guideline. METHODS: We performed a retrospective study among 300 couples that completed their first IUI cycle, using father’s fresh sperm as a result of cervical infertility, relative male factor infertility, anovulation or unexplained infertility. Pregnancy rates were compared between the patients characterized as having normal and abnormal sperm morphology values according to the previous and the recent WHO reference values and the number of inseminated motile sperm was compared between the patients who did and did not achieve a pregnancy. RESULTS: The overall pregnancy rate was 12.3%. Women older than 35 years showed a lower pregnancy rate as compared to women younger than 35 years (6.5% vs 18.2%, p 0.017). The presence of two or more preovulatory follicles on the day of hCG administration resulted in higher pregnancy rate when compared to cases in which only one preovulatory follicle was present (18.6% vs 8.2%, p 0.011). There were no significant differences between the mean total number of inseminated sperm (26.4 21.7 vs 34.86 33.12, p 0.1237) and the mean number of inseminated motile sperm (22.3 18.6 vs 27.0 24.5, p 0.3156) between the patients who did and did not achieve a pregnancy. The number of inseminated motile sperm 1x106 M/mL positively influenced pregnancy occurrence (OD: 1.47; CI: 0.88–3.14, p 0.027). Pregnancy rates did not differed neither when the male partners were characterized as having normal or abnormal sperm morphology according to the previous WHO reference values (9.8% vs 11.6%, p 0.6584), nor when the male partners were characterized as having normal or abnormal sperm morphology according to the recent WHO reference values (9.4% vs 11.3%, p 0.7469). Finally, normal sperm morphology had no influence on pregnancy rate (OD: 1.05; CI: 0.56–3.02, p 0.936). CONCLUSIONS: Our results suggest that even after the establishment of new reference values for semen parameters, sperm morphological normalcy still does not have any predictive value on IUI outcomes.