Quick answer: FSH (follicle-stimulating hormone) is made by the pituitary gland and stimulates egg development in women and sperm production in men. FSH rises as ovarian reserve declines, so it is used to help assess perimenopause, menopause and fertility. Low FSH can point to pituitary or hypothalamic issues. In women, FSH is usually tested early in the cycle.
What is FSH?
FSH is a pituitary hormone that signals the ovaries to develop follicles and the testes to produce sperm. This marker is part of the Healthspan Assessment panel available to my 1-on-1 patients.
Why FSH matters
- Egg development and ovulation
- Sperm production
- Assessing ovarian reserve and menopause
- Evaluating fertility
Understanding your result
Reference ranges vary by lab, age and sex. Your provider interprets your result against the lab’s range and your overall picture, rather than chasing a single number. Functional labs are optional. They can be helpful in more complex cases, and in my practice they are available only to patients working 1-on-1 with me.
What low FSH can mean
- Hypothalamic amenorrhea (from under-eating, stress or over-exercise)
- Pituitary disorders
- PCOS (FSH may be low relative to LH)
What high FSH can mean
- Declining ovarian reserve or perimenopause
- Menopause
- Primary ovarian insufficiency
- In men, testicular issues
What affects FSH
- Cycle day
- Age
- Hormonal birth control
- Stress and energy availability
Ways to support healthy levels
- Eat enough to support your activity level
- Manage stress and sleep (see natural hormone balance)
- Discuss fertility testing such as AMH with your provider
- Avoid smoking, which affects ovarian function
FSH and healthy aging
Rising FSH reflects aging of the ovaries, one of the clearest examples of stem cell and tissue aging in the body, and it signals hormone changes that affect bone, heart and brain.
Related tests and articles: LH, estradiol.
When to see a naturopathic doctor
- Irregular cycles or perimenopause symptoms
- Trying to conceive
- Missed periods
- Men with fertility concerns
See a medical provider promptly for no period for three months (after ruling out pregnancy), severe headaches with vision changes, or milky nipple discharge.
Want help making sense of your labs?
A free 15-minute consultation with Dr. Kneessi. No cost, no obligation. In-office in Odenton, MD or by telehealth.
Frequently asked questions
What does high FSH mean?
In women it often reflects declining ovarian reserve or menopause.
When should FSH be tested?
Usually on cycle day 2 to 4 in cycling women.
Can FSH diagnose menopause?
It can support the picture, but menopause is usually diagnosed by symptoms and 12 months without a period.
Does birth control affect FSH?
Yes. Hormonal birth control suppresses FSH.
Sources
This article is for educational purposes only and is not medical advice. It does not replace an individual evaluation. Talk with your healthcare provider before starting supplements or changing medications, especially if you are pregnant, nursing, or managing a health condition.
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