PREDICTIVE VALUE OF MORPHOLOGICALLY NORMAL SPERM CONCENTRATION IN THEMEDIUM FOR INVITRO FERTILIZATION

Morphological evaluation of spermatozoa using strict criteria (MEUSC) and conventional sperm parameters were studied with respect to in-vitr o fertilization and pregnancy outcome before and after a swim-up selec tion procedure. Recovered oocytes were inseminated with 50 000 progres sively motile spermatozoa, and this study assess the influence of the total number of spermatozoa and of the percentage with strictly normal morphology in the insemination sample on the outcome of IVF. The resu lts showed that the percentages of spermatozoa with normal morphology using strict criteria, both in native and in post-swim-up samples, wer e the best predictors of IVF outcome. Their respective cut-off points were 5% and 8%. The number of morphologically normal spermatozoa insem inated also showed a good correlation with fertilization. However, it was not possible to find a proper cut-off point for this parameter. Th e patients were categorized on the basis of their native and post-swim -up scores. Category 1, in which both parameters were below their resp ective cut-off points, showed a 7% fertilization rate and a 0% pregnan cy rate. Category 3, in which both parameters were above their cut-off points, showed a 70% fertilization rate and a 23% pregnancy rate. Thi s suggests that sperm morphology can be used as a criterion for patien t selection for IVF as an aid to identification of possibly subfertile males.