THE SPERM DEFORMITY INDEX - A RELIABLE PREDICTOR OF THE OUTCOME OF OOCYTE FERTILIZATION IN-VITRO

Objective: To evaluate a novel expression of sperm morphological param eters, tile sperm deformity index, as a predictor of fertilization ill vitro, Design: Prospective blind clinical trial. Setting: Academic te rtiary referral center. Intervention(s): Detailed sperm morphological assessment applying strict morphological criteria and a multiple entry technique ibr an unselected male population undergoing NF. The sperm deformity index, defined as the average number of deformities per sper m assessed, was calculated. Patient(s): One hundred fifty-eight; patie nts undergoing IVF treatment, Females with conditions negatively influ encing fertilization were excluded, Main Outcome Measure(s): Fertiliza tion rates and pregnancy. Result(s): Seventy-three percent of patients achieved fertilization, Patients achieving fertilization had a signif icantly higher median proportion of normal forms and a significantly l ower median sperm deformity index than the nonfertilizers. The receive r operator characteristic (ROC) curves identified cutoff points that m aximized the sum of sensitivity and specificity at sperm deformity ind ex 1.6 and normal forms 4%. The sperm deformity index had a greater se nsitivity (96%), specificity (72%), positive predictive value (90%), a nd negative predictive value (86%) than the proportion of normal sperm morphology (87%, 69%, 89%, 66%, respectively) at the optimal cutoff p oints. The area under the ROC curve was greater for the sperm deformit y index (0.875) than for the proportion of normal sperm morphology (0. 622). Achieving pregnancy did not correlate with sperm morphology. Con clusion(s): The sperm deformity index is a more reliable predictor of the outcome of fertilization in vitro than the proportion of normal sp erm morphology and can assist to identify patients who require techniq ues such as intracytoplasmic sperm injection.