Androstenedione

Androstenedione is a steroid hormone that is made in the adrenal glands and in the ovaries or testicles. The body can convert it into testosterone and into estrogen. Together with DHEA-S and testosterone, the value shows whether extra production of male hormones comes mainly from the adrenal glands or from the ovaries. The value is highest in the morning, which is why blood is preferably drawn early in the morning.

• Too much male hormone in women with excess hair growth, acne, irregular periods or signs of masculinization
• Distinguishing between extra production in the adrenal glands and in the ovaries, together with DHEA-S and testosterone
• Congenital adrenal hyperplasia (CAH): an inherited disorder in the production of adrenal hormones, and monitoring of its treatment
• Rarely: a tumor of the adrenal gland, ovary or testicle that makes male hormones

• Have your blood taken in the morning. Do you have a menstrual cycle? Then choose day 3 to 7 of your cycle.

With a raised value, the GP assesses the symptoms, medicines and supplements and the other male hormones, and if needed has 17-hydroxyprogesterone measured to detect CAH. If PCOS is suspected, an assessment of the cycle follows and possibly an ultrasound via the gynecologist. With a strongly raised value or rapidly developing masculinization, prompt referral follows to an endocrinologist (internist specializing in hormones) or gynecologist.

Androstenedione is a supplementary test, not a stand-alone test for a diagnosis. When PCOS is suspected, the Dutch PCOS guideline (NVOG, 2023) advises first measuring calculated free testosterone; androstenedione and DHEA-S have only limited value for that diagnosis, but can help if free testosterone is not abnormal or if another cause is suspected. In CAH, the specialist uses androstenedione together with 17-hydroxyprogesterone. In people without symptoms, a slightly abnormal value is hard to interpret.

• Timing: the value is highest early in the morning; a sample taken at that time is best compared with the reference values.
• Hormonal contraception interferes with the assessment of male hormones; the PCOS guideline advises stopping for at least 3 months beforehand, with a non-hormonal alternative.
• DHEA supplements, androstenedione preparations and anabolic substances raise the value; corticosteroids lower it.
• Reference values differ per laboratory, measurement method, age and sex; only compare a result with the values of the same laboratory.

Excess hair growth occurs in about 5 in 100 women; the most common cause of too much male hormone is PCOS. The severe, inherited form of CAH is diagnosed in 12 to 15 children a year in the Netherlands, nowadays usually through the newborn heel prick; the mild form only becomes noticeable in adulthood. Hormone-producing tumors of the adrenal gland or ovary are rare.

Useful for women with excess hair growth, acne, irregular periods or signs of masculinization, as an addition to testosterone and SHBG, especially if free testosterone is not abnormal. Also usable in people with CAH to monitor treatment, in consultation with the treating specialist. Not useful for people without symptoms and not as a measure of muscle building or vitality.

• A slightly raised value without symptoms can lead to unnecessary worry about the adrenal glands and to unnecessary follow-up testing.

• NVKC, allesovertesten.nl: Androsteendion
• NVOG, Richtlijn PCOS (adaptatie internationale richtlijn, 2023): module Biochemisch hyperandrogenisme
• Maastricht UMC+, afdeling Endocrinologie: Congenitale bijnierhyperplasie
• Maastricht UMC+, afdeling Endocrinologie: Hirsutisme
• Thuisarts.nl: Te veel haargroei (overbeharing)