The Test Sample
What is being tested?
Androstenedione is an androgen, one of several "male" sex hormones that are responsible for the onset of sexual differentiation in males and females and the development of secondary male physical characteristics such as a deep voice and facial hair. Though it is considered to be a "male" sex hormone, it is present in the blood of both men and women and is a precursor that can be converted by the body into more potent androgens, such as testosterone, or converted into the female hormone estrogen. This test measures the amount of androstenedione in the blood.
Androstenedione is produced by the ovaries in women, the testicles in men, and by the adrenal glands in both. Adrenal gland secretion of androstenedione is stimulated by the pituitary hormone adrenocorticotropic hormone (ACTH). The level of androstenedione in the blood will vary during the day in a "diurnal pattern," and it will vary during a woman's menstrual cycle. Because of its origins, androstenedione can be useful as a marker of adrenal gland function, of androgen production, and of the function of the ovaries or testicles. An androstenedione test is often performed after results of other tests, such as testosterone or 17-hydroxyprogesterone, are found to be abnormal.
An excess level of androstenedione and other androgens can cause children to have sex organs that are not clearly male or female (ambiguous external genitalia), excess body hair (hirsutism), and abnormal menstrual periods in girls and precocious (early) puberty in boys.
Adrenal tumors, ACTH-producing tumors, and adrenal hyperplasia can lead to the overproduction of androstenedione. While elevated levels may not be noticed in adult men, they can lead to noticeable male physical characteristics (virilization) and a lack of monthly menstrual periods (amenorrhea) in females.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
In menstruating women, the sample should be collected one week before or after a menstrual period, or as instructed.