Follicle-Stimulating Hormone (FSH) Levels Test Test
This test measures the level of follicle-stimulating hormone (FSH) in your blood. FSH is a hormone that controls sexual development and fertility. The test helps diagnose conditions that cause too much or too little FSH, such as infertility, menopause, or pituitary disorders.
What this test measures
This test measures the level of follicle-stimulating hormone (FSH) in a sample of your blood. FSH plays an important role in sexual development in children and fertility in adults.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
Higher levels of FSH are often a sign of a condition in the reproductive glands (ovaries or testicles) that prevents them from making normal levels of sex hormones. Conditions linked to high FSH include primary ovarian insufficiency, menopause, polycystic ovary syndrome, testicular injury, and certain chromosomal disorders.
Lower-than-normal results
Lower than normal levels of FSH are often a sign of a problem with the pituitary gland or hypothalamus. In women, low FSH may also be linked to rapid weight loss, being very underweight, or extreme exercise.
Frequently asked questions
What is FSH?
FSH stands for follicle-stimulating hormone. It is a chemical messenger that controls sexual development and fertility.
Why is an FSH test done in women?
In women, an FSH test may be used to help find the cause of infertility, check for conditions affecting the ovaries, find the reason for irregular periods, or determine if menopause has begun.
Why is an FSH test done in men?
In men, an FSH test may be used to help find the cause of infertility, find the reason for a low sperm count, or check for conditions affecting the testicles.
What do high FSH levels mean in children?
In children with early signs of puberty, high FSH and LH levels usually mean the child has early puberty (precocious puberty). In most cases, the cause is unknown, but it may be due to a brain tumor, injury, or infection.
What do low or normal FSH levels mean in teens with delayed puberty?
In teens with no signs of sexual development by age 13 for girls or age 14 for boys, low or normal FSH and LH levels usually mean delayed puberty. Many teens with delayed puberty are healthy, but it may be caused by conditions like poor nutrition, hypogonadism, or genetic disorders.
Related lab tests
Sources
- MedlinePlus: Follicle-Stimulating Hormone (FSH) Levels Test — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.