17-OH progesterone blood test in Chiswick

What the test measures

17-hydroxyprogesterone (17-OHP) is a steroid hormone made by the adrenal glands, and in smaller amounts by the ovaries and testes. It is a stepping stone in the pathway the adrenal glands use to make cortisol. If an enzyme in this pathway, usually 21-hydroxylase, is not working fully, 17-OHP builds up and the body diverts more of it into making androgens, the hormones linked to male characteristics.

In its classic form, congenital adrenal hyperplasia (CAH) is found in newborns. A milder, non-classic form may only show itself in later childhood or adulthood, with signs that can resemble polycystic ovary syndrome (PCOS), such as irregular periods, excess facial or body hair, acne and difficulty conceiving. Measuring 17-OHP helps tell these apart.

The price includes the blood sample at our Chiswick clinic, analysis at the Randox accredited laboratory, a practitioner review of your result and a GP feedback report on request.

Who it is for

• You have irregular or absent periods together with excess hair growth or acne.
• You have been told you may have PCOS and your doctor wants to exclude other causes.
• Your androgen levels, such as testosterone or androstenedione, have come back raised.
• A family member has congenital adrenal hyperplasia.
• You are having difficulty conceiving and your hormone picture is being reviewed.

Understanding your result

Your report shows the laboratory reference range, and the result is read with your symptoms, cycle and other hormones. A raised level can point towards non-classic CAH, but it also rises naturally after ovulation and in pregnancy, so timing matters. Borderline results are common, and a specialist may arrange a stimulation test to confirm or exclude CAH. A low or normal level, taken at the right time, makes CAH less likely.

The result is a prompt for discussion, not a diagnosis, and your practitioner can suggest when to involve your GP or an endocrinologist.

Preparing for your test

Book an early morning appointment, ideally before 9am, as levels are highest then. If you have periods, the test is best taken in the early follicular phase, on day 2 to 5 of your cycle. Steroid medicines, including some creams and inhalers, and hormonal contraception can affect results, so please tell us what you take. No fasting is needed.

For a wider view of your hormones, our hormone health check includes reproductive and thyroid markers, and our testosterone tests help assess androgen levels. See every blood test and price in Chiswick.

Questions

How much is a 17-OH progesterone test in Chiswick?

The 17-OH Progesterone test costs £159 at Omnia Lifestyle in Chiswick. It includes the blood sample, laboratory analysis, a practitioner review of your result and a GP feedback report if you would like one.

Is 17-OH progesterone the same as progesterone?

No. They are related hormones, but progesterone mainly reflects ovulation and pregnancy, while 17-OHP is used to check the adrenal pathway that makes cortisol.

Can this test diagnose PCOS?

No single blood test diagnoses PCOS. 17-OHP helps exclude CAH, which can look similar, so that PCOS can be considered with more confidence.

Can men have this test?

Yes. It is less common, but it can be useful if a man has early puberty signs, fertility concerns or a family history of CAH.