Scanning electron microscopy of human sperms after preparation of semen for in-vitro fertilization.

Ultrastructural changes of human sperms after routine preparation for in-vitro fertilization were examined by scanning electron microscopy. Studies were performed with freshly ejaculated semen of 21 normozoospermic patients. Spermatozoa were analysed at 10000-fold (sperm head with acrosome, postacrosomal border and postnuclear cap) and 2500-fold (midpiece and endpiece of sperm tail) magnification. Compared with untreated specimens, slight membrane damage was found after routine washing and centrifugation procedures in swim-up preparations. However, on the basis of a score system for quantification of morphologic data, no statistically significant differences existed between untreated semen and swim-up preparations. We conclude that, with normozoospermic semen, the rate of ultrastructural damage attributable to sperm-washing procedures is too low to be of clinical consequence.