New Study Redefines Normal Testosterone Ranges for Women

A range that changes with age

If you have ever had your testosterone checked, your lab report probably compared your result with one range for every adult woman, whether you are 25 or 55. A study published in September 2026 in the Journal of Endocrinological Investigation suggests that is not the best way to read the number.

Researchers at University College London, Imperial College London and Hertility Health, a UK hormone-testing company where most of the authors work, looked at testosterone results from 5,323 healthy women aged 19 to 59. Everyone had regular cycles and a normal BMI, used no hormonal contraception, and had no history of PCOS or thyroid conditions. Each woman was tested the same way: a finger-prick blood sample on day three of her cycle, after fasting, measured in one accredited lab.

What they found

• Testosterone falls steadily through adult life, by about 1.4% a year on average.
• The spread between women widens with age, so what is typical at 25 is not what is typical at 50.
• Women who reported excess hair growth had higher levels on average than the reference group.

The authors conclude that a woman's result is best compared with healthy women of a similar age, and they published reference ranges for every age from 18 to 60. For example, 95% of the 30-year-olds in the study had a total testosterone between about 0.34 and 2.50 nmol/L (roughly 10 to 72 ng/dL). At 50, the range was about 0.17 to 2.08 nmol/L (roughly 5 to 60 ng/dL).

We have put the study's ranges for each age into one table on our page about testosterone levels in women by age, with the US units many labs use.

What to keep in mind

• Labs measure testosterone in different ways. This study used a widely used immunoassay. Labs using other methods may print different ranges, so compare your result with the range on your own report.
• The study covers women who still have regular cycles. It does not describe levels after menopause.
• A number is one piece of the picture. Your prescriber reads it alongside your age, cycle timing, symptoms and related labs such as free testosterone and SHBG. Our hormone lab guide lists the tests many prescribers order.

Where we come in

We are a pharmacy, not a prescriber, so we do not interpret lab results. If your prescriber prescribes testosterone, we prepare it to order as a hypoallergenic cream or an olive oil base topical, and we ship to all 50 states and the District of Columbia. Our page on compounded testosterone for women explains how your prescription reaches us. Questions? Call us at 423-975-0597.

Source: Wainwright E, Getreu N, et al. Redefining testosterone reference ranges for adult females. J Endocrinol Invest. 2026;49(9):2339-2349. Compounded preparations are not reviewed or approved by the FDA for safety or efficacy. This article is for education and is not medical advice.