The prevalence and diagnosis rates of Klinefelter syndrome: an Australian comparison

To determine the prevalence and diagnosis rates of Klinefelter syndrome (KS) in Victoria, Australia, and compare these to previous international findings.

A Victorian population-based descriptive study of all cytogenetic examinations resulting in a diagnosis of KS, including prenatal diagnoses from 1986 to 2006 and postnatal diagnoses from 1991 to 2006.

Birth prevalence and diagnosis rates of KS.

The birth prevalence of KS in Victoria is estimated to be 223 per 100,000 males (95% CI, 195-254), with about 50% of cases remaining undiagnosed.

KS may be occurring more frequently than has been reported previously, yet many cases remain undiagnosed. Our results highlight the need for increased awareness leading to timely detection.