[Which technique is best for which male infertility?].

To what extent are sperm analyses valid? Does a normality benchmark exist? Analysis of the literature suggests that the normal values for semen parameters defined by the WHO may require reassessment. Other criteria should perhaps be taken into account, such as chromatin or DNA abnormalities. The existing studies are contradictory and the DNA fragmentation rate is not used by the ASRM as a predictor of the pregnancy rate. Several teams have attempted to suggest threshold values for semen parameters, both in cases of intrauterine insemination and ICSI. In the case of IUI, the results are highly variable depending on the study in question. As for ICSI, although there is some consensus of opinion in the data, other findings are controversial or debatable. However, there are few properly conducted randomised prospective studies and very few multivariate analyses.