Validity of a rapid assay for antisperm antibodies in semen.

OBJECTIVE To determine the validity of a rapid assay for antisperm antibodies in semen. DESIGN Prospective comparison of the results of standard and rapid antisperm antibody assays performed simultaneously. SETTING Tertiary care infertility center. PATIENT(S) Couples who presented for infertility evaluation. INTERVENTION(S) Semen analysis and measurement of antisperm antibodies in semen using a standard and a rapid immunobead binding test (IBT). MAIN OUTCOME MEASURE(S) [1] Comparison of sperm parameters between semen-containing antisperm antibodies and semen free of antisperm antibodies. [2] Validation of the rapid test by calculation of sensitivity, specificity, positive and negative predictive values of the rapid assay using the standard assay as a gold standard. [3] Cost comparison of the standard and rapid test. RESULT(S) [1] Nine semen specimens with antisperm antibodies had a significantly lower sperm concentration, motility, and total motile fraction compared to 44 specimens without antisperm antibodies. Also, specimens with antisperm antibodies had a significantly higher percentage of vibratory sperm and percent of bound antisperm antibodies. The strict morphology, liquefaction time, semen volume, and white blood cell concentration were no different between the two groups. [2] Using a threshold of > or =12% of bound antisperm antibodies in the rapid assay, the sensitivity, specificity, positive and negative predictive values of the test are 100% when correlated with a threshold of > or =20% in the standard assay. Increasing the threshold in the standard assay decreases the specificity and positive predictive value of the rapid assay but not the sensitivity and the negative predictive value. [3] The cost of the rapid assay was 16% that of the standard test and its performance took 20% of the time it took to set and perform the standard test. CONCLUSION(S) A rapid test for antisperm antibodies is valid, reliable, and more cost and labor effective than a standard IBT.