Androstenedione is a steroid hormone produced by the adrenal glands and the gonads — the testes in men and the ovaries in women. It sits at a key junction in the hormonal production pathway, serving as a direct precursor to both testosterone and oestrogen. Because of this central position, its levels can influence the balance of sex hormones throughout the body.

In women, elevated androstenedione is one of the most common hormonal findings in polycystic ovarian syndrome (PCOS) and congenital adrenal hyperplasia, and can contribute to symptoms such as irregular periods, acne, and excess hair growth. In men, it contributes to the overall androgen pool alongside testosterone and DHEAS.