---

Background: Klinefelter syndrome (KS) also known as 47, XXY is one of the most prevalent chromosomal abnormalities among men. Infertility is one of the most primary features of this condition. However, there are some other associated features such as thin and tall appearance, absent, delayed or incomplete puberty, small and firm testicles, small penis and gynecomastia.
Case description: We herein report a patient with mosaic KS whose karyotype consisted of 47, XXY/46, XY. The case’s wife had two miscarriages, followed by a healthy girl with a normal karyotype who was born taller than the average at the age of two.
Conclusion: Mosaic KS dramatically increases the chance of having healthy offspring with normal genetic patterns without performing artificial insemination methods compared to those with complete KS.