Until a few years ago, Klinefelter syndrome with a homogeneous 47.XXY karyotype was considered a model of absolute male sterility. In this review, we will discuss: (1) potential fertility following TEsticular Sperm Extraction-IntraCytoplasmic Sperm Injection (TESE-ICSI), (2) the physiopathology of spermatogenic failure and the origin of focal spermatogenesis and risk of aneuploidy in potential offspring, (3) the advantage of searching for and cryopreserving spermatozoa in adolescent instead of adult patients. In previous published series, TESE was successful in almost 50% of patients and pregnancy rate following ICSI was not obviously different from other causes of spermatogenic failure. The rate of positive sperm extraction seemed to be better for younger patients. During childhood, the survival rate of 47.XXY spermatogonia is low. However, a few spermatogonia are able to eliminate their extra X chromosome, giving rise to rare clones of 46.XY gonia which are the origin of rare foci of complete spermatogenesis after puberty. Several arguments suggest that this focal spermatogenesis decreases with age. This suggests there would be a benefit to patients if TESE were performed in adolescences and spermatozoa were cryopreserved. In addition, androgenotherapy is a common treatment of Klinfelter syndrome but carries a risk of decreasing focal spermatogenesis by lowering gonadotropins. Preservation of spermatozoa from adolescence by TESE would allow androgenotherapy to be prescribed with less concern for future reproductive capacity. Controlled studies should be done to determine the best age for TESE-ICSI in 47.XXY homogeneous Klinefelter syndrome patients.
Copyright © 2010. Published by Elsevier Masson SAS.