The test for follicle-stimulating hormone (FSH), a hormone associated with reproduction and the development of eggs in women and sperm in men, has several uses.

In both women and men, the test may be used with other hormone tests such as luteinizing hormone (LH)testosteroneestradiol, and/or progesterone to help:

  • Determine the cause of infertility
  • Diagnose conditions associated with dysfunction of the ovaries or testicles
  • Aid in the diagnosis of pituitary or hypothalamus disorders, which can affect FSH production

In women, FSH levels are also useful in:

  • The investigation of menstrual irregularities
  • Predicting onset or confirmation of menopause

In men, FSH levels are used to help determine the reason for a low sperm count.

In children, FSH and LH are used to help diagnose delayed or precocious (early) puberty. Irregular timing of puberty may be an indication of a more serious problem involving the hypothalamus, the pituitary gland, the ovaries or testicles, or other systems. The measurement of LH and FSH may differentiate between benign symptoms and true disease. Once it is established that symptoms are a result of true disease, further testing can be done to discern the underlying cause.