Submicroscopic mathematical evaluation of spermatozoa in assisted reproduction. 3. Partial zona dissection (PZD)...

This paper belongs to a series of application of the Baccetti's et al. (1995) formula to the submicroscopical mathematical examination of the human spermatozoa used for assisted reproduction. The present experiment concerns partial zona dissection, a technique requiring a careful evaluation of sperm quality in order to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of PZD. In fact the two numbers concerning the sperm ultrastructural quality (percentage and total number of spermatozoa free from defects in the ejaculate) obtained in successful and unsuccessful PZD groups, showed a large difference (P < 0.01). The most important characteristics seem to be the quality of the acrosomal complex, the condition of the chromatin and the mitochondrial assembly. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (from P < 0.05 to P < 0.01). A comparison with the results previously obtained in ICSI (Strehler et al., 1995) and IVF (Piomboni et al., 1996) shows that sperm quality is significantly more implicated in the success of IVF than of PZD or ICSI.