Аннотация
Klinefelter syndrome (KS) is a genetic condition that results from male with one or more extra copy of the X chromosome.The primary features are infertility and small, poorly functioning testicles.Symptoms also include greater height, less body hair, weaker muscles, poor coordination, enlarged breast tissue, and less interest in sex.We present the case of a 36-year-old man who is KS with normal clinical and laboratory phenotype, which is a very rare finding in this syndrome.Most men with KS are infertility, they produce little or no sperm.Assisted reproductive procedures may help some men with KS to father a child.But the necessity of PGD during assisted reproductive treatment has always been a controversial topic.In this case, we examined five blastocysts of patient, two of them with abnormal karyotype and other three were normal.Therefore, it is necessary to carry out preimplantation genetic diagnosis for KS patients before implantation, even though their phenotypes are normal.