Follicle Stimulating Hormone and Luteinizing Hormone (FSH and LH)

FSH and LH are hormones made by the pituitary gland in the brain that control the reproductive system. In women, they regulate the menstrual cycle and ovulation; in men, they support sperm production and testosterone levels. When these hormones are too high, it may mean the ovaries or testes are not functioning properly. When they are too low, it may suggest the brain is not sending the right signals to the reproductive organs. Your doctor will interpret these results alongside other hormone tests and your personal health history to understand what they mean for you.

When elevated: Elevated FSH and LH levels typically indicate primary gonadal insufficiency, premature ovarian insufficiency, or natural menopause in women. High gonadotropins in men suggest primary testicular failure. Isolated FSH elevation may reflect diminished ovarian reserve. In children, elevated gonadotropins may indicate central precocious puberty. When low: Low FSH and LH levels suggest hypothalamic or pituitary dysfunction, including conditions such as hypothalamic amenorrhea, hyperprolactinemia, pituitary adenoma, or Kallmann syndrome. Suppressed gonadotropins are also seen with exogenous sex steroid use, including anabolic steroids or hormonal contraceptives. Low levels in the context of low sex steroids indicate secondary or tertiary hypogonadism.

FSH and LH are relevant to athletes primarily for monitoring reproductive health and hormonal balance during intense training. Chronically elevated training stress can suppress these hormones and disrupt menstrual cycles in female athletes or reduce testosterone production in males, signaling overtraining or inadequate recovery.