[Evaluation and preparation of gametes]

The aim of this paper is to review some topics related to the management and evaluation of the male and female gametes to be used in any assisted reproduction procedure. First, the international criteria for the quantitative morphological and biochemical evaluation of the semen samples are presented, both for the initial analysis and when chosen procedure is performed. Next, we discuss the biochemical characteristics of the solutions used to in vitro induce capacitation and acrosome reaction, indispensable events previous to the in vivo or in vitro interaction of the gametes. We also present the methodology for the in vitro management of the spermatozoa and to evaluate the efficiency of these cells to achieve in vitro acrosome reaction, as well as the utilization of the zone-free hamster egg penetration test to evaluate the human sperm capacity to penetrate the female gamete. Finally, the morphological characteristics of the cumulus oophorus-corona radiate-zona pellucida-vitellus complexes are analyzed, as well as the biochemical and hormonal composition aspiration, in order to assess the quality of the recovered oocytes, their probabilities to be fertilized and their potential to develop into subsequent stages which culminate with the birth of full term, viable and healthy babies.