Preimplantation diagnosis for X and Y normality in embryos from three Klinefelter patients

In some 47,XXY Klinefelter patients without evidence of mosaicism, testicular spermatozoa can be successfully recovered and used for intracytoplasmic sperm injection (ICSI). To ensure the replacement of embryos with a normal X and Y chromosome pattern, preimplantation diagnosis can be performed. This paper reports on three 47,XXY Klinefelter patients from whom it was possible to retrieve testicular spermatozoa in order to perform ICSI. From their healthy wives a total of 27 oocyte-cumulus complexes were retrieved from which 22 metaphase-II oocytes were obtained and injected; 19 of these were intact after injection. Two distinct pronuclei were observed in eight oocytes (42.1%) 18 h after injection. On day 3 of development, five embryos (62.5%) had reached at least the 6-cell stage and were of sufficient quality to undergo biopsy and subsequent preimplantation diagnosis for sex chromosome analysis by fluorescent in-situ hybridization. The four embryos diagnosed as normal were transferred to three respective patients, resulting in one biochemical pregnancy. The remaining cells of the fifth embryo were analysed afterwards, revealing a normal X and Y chromosome constitution. So far, in the five embryos diagnosed, a normal sex chromosome pattern has been observed.