[Etiology and treatment of sterility due to azoospermia]

Azoospermia can be classified according to the serum level of FSH into obstructive (OA) or non-obstructive (NOA) azoospermia. It can also be due to a lack of gonadotrophins. In the latter case the administration of FSH and HCG can normalize the sperm production. In the other cases ICSI must be performed. In OA sperm can be retrieved using percutaneous epididymal aspiration or testicular fine needle aspiration in case of failure of vasovasostomy or epididymovasostomy. In NOA or spermatogenic arrest, focal spermatogenesis can be observed in 40 to 50% of cases using repeated testis biopsies, allowing to perform ICSI. Although the risk of malformation in children born after ICSI is not increased there is an increased risk to transmit genetic abnormalities in case of NOA (such as the rate of sex chromosome, or microdeletions of the Y chromosome) and in case of congenital OA (mutations of the cystic fibrosis gene).