RESUMO
BACKGROUND: Klinefelter's syndrome is one of the major causes of azoospermia, cryptozoospermia and severe oligozoospermia with either a nonmosaic (47,XXY) or mosaic (47,XXY/46,XY) ICSI treatment with cryopreserved testicular spermatozoa failed, but after the third attempt, 6 of 8 oocytes injected with cryopreserved sperm were fertilized and karyotype. Men with Klinefelter's syndrome generally have difficulty having children. CASES: Patient 1 had motile spermatozoa in the ejaculate, which were injected into 3 oocytes, resulting in fertilization and cleavage. Two good-quality embryos were transferred into his wife's uterine cavity. She conceived and, following a normal pregnancy, delivered a healthy female infant. Two years later she conceived for the second time with motile spermatozoa in the ejaculate and delivered a healthy male infant uneventfully. To our knowledge, this was the first case in which a nonmosaic Kleinefelter's syndrome patient fathered 2 children through intracytoplasmic sperm injection (ICSI) using motile spermatozoa in the ejaculate. Patient 2, with azoospermia, was subjected to testicular biopsy to collect spermatozoa. The first 2 attempts at ICSI treatment with cryopreserved testicular spermatozoa failed, but after the third attempt, 6 of 8 oocytes injected with cryopreserved sperm were fertilized and cleaved. Two of these embryos were transferred into the wife's uterine cavity. She conceived and, following a normal pregnancy, delivered a healthy male infant. In all cases, amniocentesis followed by genetic analysis showed a normal karyotype. CONCLUSION: Two infertile men with nonmosaic Klinefelter's syndrome successfully fathered normal children after intracytoplasmic injection of ejaculated or testicular spermatozoa.