FACTORS AFFECTING SPERM YIELD DURING SWIM-UP

Purpose: The migration of sperm (expressed as the percentage of the to tal motile cells in the ejaculate aliquot) from seminal plasma into ov erlying medium (swim-up) was increased with time, temperature, and inc reasing the surface area of contact between the two phases by increasi ng the angle of tube inclination. Results: The proportion of sperm mig rating into the medium was relatively constant with varying sperm coun t. Stimulation of the progressive motility of spermatozoa in vitro usi ng a motility enhancing drug (2-deoxyadenosine) increased sperm migrat ion initially but no more than the maximum reached by controls after e xtended incubation. Conclusion: Sperm yield from normozoospermic men a nd men with borderline asthenoteratozoospermia represented approximate ly 40 and 15% of the total motile cells in the ejaculate aliquots, res pectively. In general, in both groups spermatozoa in the swim-up fract ion exhibited superior motility, vitality, and morphology compared to the original ejaculates. Tail abnormalities were reduced more than hea d abnormalities and subjects with borderline sperm qualities exhibited less dramatic improvements in quality than the normozoospermic indivi duals.