Relationship of hamster ovum sperm penetration assay to seminal fluid analyses in the evaluation of infertile couples.

The males of 279 infertile couples were evaluated with hamster ovum sperm penetration assay (SPA) and seminal fluid analysis. The mean SPA score for the total population was 23.0% penetration with a range of 0-97%. Twenty five percent of the patients demonstrated scores within the abnormal range (0-10%), and 15% were in the "equivocal" range (11-14%). Comparing each individual with the total population using linear regression analysis, it was noted that sperm concentration, percent motility, and percent oval forms varied directly with the SPA, and the slopes of the relationships are positive and statistically significant (p less than 0.0001, 0.002, and 0.0001, respectively). The relationship between SPA and volume is not statistically significant (p greater than or equal to 0.354). To determine whether the SPA could be utilized to establish appropriate normal parameters for various components of SFA, these were analyzed in 169 men who had SPAs of greater than or equal to 15%. Although most SFA values fell within the normal range for this group, there were several exceptions, particularly with respect to percent motility and the presence of leukocytes in the semen. Comparing the percentage of males with abnormal SPA in groups of couples with or without a demonstrable abnormality affecting fertility in the wife, no statistically significant differences could be found. The value of the SPA and SFA in investigating males of infertile couples is discussed.