Androstenedione is a steroid in the androgen family, the male hormones responsible for sexual differentiation and the development of secondary male characteristics (deep voice, facial hair, etc.). Androstenedione is produced by the ovaries in women, by the testicles in men and by the adrenal glands in both sexes. Androstenedione levels vary throughout the day and throughout the menstrual cycle. Androstenedione is a useful indicator of adrenal gland, ovarian and testicular function.
High levels of androstenedione can be an indication of overactive adrenal glands (tumour or cancer), ovaries (polycystic ovaries) or testicles. Slight variations in levels are generally meaningless. High levels can be associated with hyperplasia (congenital or other), tumour or, more rarely, adrenal cancer. High levels are not diagnostic of a specific condition, rather they indicate the need for further investigation to determine the cause.
Abnormally low levels of androstenedione may be the result of adrenal gland, ovarian or testicular insufficiency. In individuals being treated with glucocorticoids for congenital adrenal hyperplasia, normal levels of androstenedione indicate that the treatment is effective and is properly controlling the excess androgen production associated with this condition.