Turner syndrome is a female-only genetic disorder that affects about 1 in every 2,000 baby girls.
A girl with Turner syndrome only has one normal X sex chromosome, rather than the usual two.
This chromosome variation happens randomly when the baby is conceived in the womb. It isn't linked to the mother's age.
Read more about the genetic cause of Turner syndrome.
Females with Turner syndrome often have a wide range of symptoms and some distinctive characteristics. Almost all girls with Turner syndrome:
As height and sexual development are the two main things affected, Turner syndrome may not be diagnosed until a girl fails to show sexual development associated with puberty, usually between the ages of 8 and 14 years.
Other characteristics of Turner syndrome can vary significantly between individuals.
There's no cure for Turner syndrome but many of the associated symptoms can be treated.
Girls and women with Turner syndrome will need to have their heart, kidneys and reproductive system checked regularly throughout their lives. However, it's usually possible to lead a relatively normal and healthy life.
Life expectancy is slightly reduced, but it can be improved with regular health checks to identify and treat potential problems at an early stage.
If you or your daughter has Turner syndrome, your clinical team will pass information about you/your daughter on to the National Congenital Anomaly and Rare Diseases Registration Service (NCARDRS).
The NCARDRS helps scientists look for better ways to prevent and treat Turner syndrome. You can opt out of the register at any time.