Multicentric, prospective observational data show sperm capacitation predicts male fertility, and cohort comparison reveals a high prevalence of impaired capacitation in men questioning their fertility

ABSTRACT Research Questions Can a previously defined relationship between sperm capacitation and the probability of a man to generate pregnancy within three cycles, prospectively predict male fertility in diverse clinical settings? What is the prevalence of impaired sperm fertilizing ability in men questioning their fertility (MQF)? Does this relate to traditional semen analysis (SA) metrics? Design Multicentric, prospective observational study: Data (n=128; 6 clinics) were analyzed to test a published relationship between the percentage of fertilization competent, capacitated sperm (Cap-Score™) and probability of generating pregnancy (PGP) within three cycles of intrauterine insemination (IUI). Logistic regression of total pregnancy outcomes (n=252) assessed fit. Cohort comparison: Cap-Scores of MQF (n=2,155; 22 clinics) were compared to 76 fertile men. Results New outcomes (n=128) were rank-ordered by Cap-Score and divided into quintiles (25-26/group); chi-square revealed no difference between predicted and observed pregnancies (p=0.809). Total outcomes (n=252; 128 new + 124 previous) were pooled and model recalculated, yielding improved fit (p Conclusion Sperm capacitation prospectively predicted male fertility. Impaired capacitation affects many MQF with normal SA results, informing diagnosis versus idiopathic infertility.