LAUSR

BACKGROUND An explosive increase in couples attending assisted reproductive technologies (ART) has been recently observed, despite an overall success rate about 20-30%. Considering the ART-related economic and psycho-social costs, the improvement of these percentages is extremely relevant. However, in the identification of predictive markers of ART success, male parameters are largely underestimated so far. STUDY DESIGN Retrospective, observational study. OBJECTIVES To evaluate whether conventional semen parameters could predict the ART success MATERIALS AND METHODS: All couples attending a single third-level Fertility Centre from 1992 to 2020 were retrospectively enrolled, collecting all semen and ART parameters of fresh cycles. Fertilization rate (FR) was the primary end-point, representing a parameter immediately dependent from male contribution. Pregnancy and live birth rates were considered in relation to semen variables. Statistical analyses were performed using the parameters obtained according to WHO manual edition used for semen analysis. RESULTS 22013 in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles were considered. Overall, FR was significantly lower in patients with abnormal semen parameters compared to normozoospermic men, irrespective to the WHO manual edition. In the IVF setting, both progressive motility (p = 0.012) and motility after capacitation (p = 0.002) significantly predicted fertilization rate (statistical accuracy = 71.1%). Sperm motilities predicted also pregnancy (p<0.001) and live birth (p = 0.001) rates. In ICSI cycles, sperm morphology predicted FR (p = 0.001, statistical accuracy = 90.3%). Sperm morphology significantly predicted both pregnancy (p<0.001) and live birth (p<0.001) rates, and a cut off of 5.5% was identified as a threshold to predict clinical pregnancy (AUC = 0.811, p<0.001). DISCUSSION Interestingly, sperm motility plays a role in predicting IVF success, while sperm morphology is the relevant parameter in ICSI cycles. These parameters may be considered reliable tools to measure the male role on ART outcomes, potentially impacting the clinical management of infertile couples. This article is protected by copyright. All rights reserved.