Helpline 0300 111 4748


Klinefelter’s Syndrome (KS)/XXY isn't rare ...but it is rarely diagnosed.  It is occurs in around 1 in 600 live male births.

Many medical professionals are unaware how common it is and often fail to diagnose it.

75% of those affected are never diagnosed. 


An early diagnosis can be life changing.

If diagnosed in childhood, appropriate support can ensure the child flourishes and reaches their potential.

Early promotion of a healthy life style can help to avoid many health problems.

Although very few men will be able to father children without assistance, there are techniques already available by which sperm could be extracted from the testes.  The procedure is more likely to be successful in younger adults.

Fertility options

People with KS have two X chromosomes and one Y chromosome (XXY). This is why the KSA refers to the condition as KS/XXY.

KS/XXY is diagnosed by a genetic blood test which identifies the karyotype i.e. the number, size and shape of the chromosomes.

Although the condition is relatively common, its effects are not well understood.

Scientific background

Common symptoms



Common health issues

Fertility options

The future

Useful links

If you would like to talk to someone please call our Helpline:

0300 111 47 48.

Please remember that as the KSA is run entirely by volunteers. Sometimes there may not be anyone available to take your call. Please leave a message with your email address or phone number and we will get back to you.


If you are feeling suicidal,  please contact the Samaritans
They are available 24 hours per day, phone: 116 123 or visit