Contributed by – Healthians Team

What is the 17-OPH test?

The 17-hydroprogesterone test (also known as the 17-OPH test) measures the amount of 17- hydroprogesterone (17-OPH) in the blood. 

17-OPH is a hormone produced by the adrenal gland, tiny glands located on top of each kidney. Along with various enzymes or proteins, 17-OHP is eventually converted to cortisol. Appropriate levels of cortisol are needed because it helps in the breakdown of protein, glucose, and lipids, and regulates blood pressure and the immune system. 

In case there is a lack of enzymes needed for the production of cortisol, cortisol deficiency can occur which in turn would cause a buildup of 17-OPH in the blood. High levels of 17-OHP indicate a genetic condition called congenital adrenal hyperplasia (CAH). Therefore, with the help of 17-hyrdoprogesterone test, the condition can be diagnosed.

Who should get tested?

The 17-OHP test is typically ordered routinely as a part of the newborn screening and may be repeated to confirm the initial results.

This test is also ordered when an infant or young child displays signs and symptoms of CAH. They include – 

  • Lack of energy
  • Not eating well
  • Dehydration
  • Low blood pressure
  • Sex organs that are not clearly visible
  • Development of male secondary sex characteristics
  • Acne 

Sometimes, this test is ordered in older children or in adults when they display symptoms of a milder form of CAH or late-onset of CAH. These symptoms include – 

  • Excess facial and body hair
  • Irregular menstruation
  • Development of male secondary sex characteristics
  • Infertility 

Why is the 17-OPH test needed?

The 17-OHP test is often used to diagnose or rule out CAH in newborns. It is also used to – 

  • diagnose CAH when symptoms are present in older children and adults who may have a milder form of the disorder.
  • monitor the effectiveness of treatment for CAH.

What does the 17-OPH test result mean?

The results of a 17-OHP test depend on various factors, including age, sex, and the method used for testing. Therefore, always get the test results checked by a doctor to correctly understand what they mean to you.

Generally, 17-OPH test normal results for various age groups are considered to be – 

  • Newborns – 1000 – 3000 ng/dL
  • Babies older than 24 hours – less than 100 ng/dL
  • Adults – less than 200 ng/dL

Anything higher than the normal range could mean the presence of CAH. 17-OHP levels are also high when an adrenal tumor is present. Hence, further testing may be required to confirm the diagnosis and find out the specific cause of increased 17-OHP levels.

How is the test done?

A small blood sample is needed for the 17-OHP test. In adults, it is usually drawn from a vein in the arm, while in infants, a simple heel prick is enough to collect an adequate blood sample. The process is quick and usually painless. The punctured site is often covered with a bandage to prevent any infection. 

Normally, any kind of special preparation or fasting before the test is not needed. However, early morning sample collection or sample collection at a specific time during a woman’s menstrual cycle may be requested by the doctor.

Know your 17-OPH levels