Non-Classical Congenital Adrenal Hyperplasia

Non-Classical Congenital Adrenal Hyperplasia

Non-classical congenital adrenal hyperplasia (NCCAH or NCAH) is a hormonal disorder characterized by early signs of puberty namely excessive hair growth, increase in height and acne. It can also involve decreased fertility as well as menstrual problems in females. This non-classical form is much milder than the classical form of CAH, and can be treated effectively using steroid hormones.

If you have just received a diagnosis there is help available – please see ‘Further information and support’ below for links to valuable resources. It is also important to note that not every person with this condition experiences all the symptoms described and it is worth talking to your doctor or other relevant healthcare specialists to discuss you or your family member’s specific case.


Non-classical congenital adrenal hyperplasia is an autosomal recessiveA pattern of inheritance in which a disorder results only when an individual inherits two copies of a specific disorder-related mutation, one from each parent. condition.


The carrier frequencyNumber that describes how many people in a population are carriers (have one altered copy of a gene and one normal copy of the same gene) for a genetic disorder. Carriers for recessive disorders are unaffected but are at risk of passing on the disorder to their children. of non-classical congenital adrenal hyperplasia is approximately 1 in 3 Ashkenazi Jews. In the wider population the carrier frequency is 1 in 100 people.

The disease frequency in Ashkenazi Jews is approximately 1 in 27.


Non-classical adrenal hyperplasia is a mild disorder with very varied symptoms that usually start to show in childhood. Some females and many males do not develop any symptoms at all.

Common signs and symptoms of NCCAH in both males and females are:

  • Early signs of puberty e.g. premature development of pubic hair
  • Excessive hairiness
  • Acne
  • Accelerated growth in children but short stature as adults
  • Advanced bone age
  • Balding

Other symptoms in females are:

  • enlarged clitoris
  • Reduced ovulation
  • Menstrual dysfunction, such as polycystic ovaries
  • Decreased fertility

Additional male symptoms are:

  • Early beard growth
  • Enlarged penis with comparatively small testes
  • Low sperm count

Non-classical adrenal hyperplasia does not cause the severe symptoms of virilisation and salt-wasting seen in classical adrenal hyperplasia.

Please click on the titles to open and close the following information sections.

Non-classical adrenal hyperplasia is caused by a mutation in a gene coding for the enzyme steroid 21-hydroxylase. When this enzyme does not function normally the body starts to produce excessive androgens.

Androgens are steroid hormones which stimulate the development of male sex organs and encourage the development of male sex characteristics. Females normally produce androgens at low levels, but an overproduction of androgens causes the symptoms of NCCAH.

Non-classical adrenal hyperplasia can be treated effectively using drugs called corticosteroids. The treatment slows growth in children and delays puberty so that it can start on time. In adult women, this treatment can be used to regulate the menstrual cycle, prevent hairiness and acne, as well as improving fertility.

Non-classical adrenal hyperplasia does not affect an individual’s lifespan.

Though the disease can be well managed women may experience menstrual problems and infertility. Adults with NNCAH have a small risk of tumours in the adrenal gland and other metabolic complications.

The disorder can be diagnosed clinically by a doctor familiar with the symptoms together with a blood test to measure the hormone levels in the blood. A genetic test, done via a simple blood test, can be used to confirm the diagnosis.

Carrier testing and prenatal testing is also available for this disorder. The test looks at the most common mutations found in the people of Ashkenazi Jewish ancestry and has a detection rate of 95% for this population.

For more details about testing, please refer to the testing section.

CAH Parent and Patient Support Group

Patients and parents often feel alone in their journey in dealing with CAH. The CAH IS US support group was founded to help and offer support as well as give both parents and older patients the chance to meet, exchange ideas and share experiences.

Living with CAH
This support organisation is a sub group of CLIMB (Children Living with Inherited Metabolic Diseases). It exists to give support to families and people with the disorder, to increase awareness of the condition to the public and to the medical profession, and to raise funds to support research.

CARES Foundation

The Congenital Adrenal Hyperplasia Research Education & Support Foundation is committed to improving lives through proactively advancing research for better understanding of CAH, better treatments and a cure, as well as through education, advocacy, resources and support services.

To find out more about general resources relevant to Jewish genetic disorders, please visit our resources and support section.


Written by Jnetics.
Approved by Professor Peter Hindmarsh, Consultant Pediatric Endocrinologist at Great Ormond Street Hospital
Last review: 08.06.2018