FSH optimal range and reference range

Compiled by Alina Radu, founder of Sera, from the published sources below · Last reviewed November 9, 2026

Sera's bands for FSH, which differ for men and women:

Female: Optimal 3 – 10 mIU/mL (3 – 10 IU/L); sufficient 1.7 – 21.5 mIU/mL (1.7 – 21.5 IU/L); out of range below 1.7 or above 21.5 mIU/mL.
Male: Optimal 2 – 8 mIU/mL (2 – 8 IU/L); sufficient 1.5 – 12.4 mIU/mL (1.5 – 12.4 IU/L); out of range below 1.5 or above 12.4 mIU/mL.

Evidence grade: Published reference interval. A band that primarily reflects a published adult laboratory or population reference interval. It is not necessarily applicable to every assay or laboratory.

All units

Unit	Applies to	Optimal	Sufficient	Out of range
mIU/mL	Female	3 – 10	1.7 – 21.5	below 1.7 or above 21.5
mIU/mL	Male	2 – 8	1.5 – 12.4	below 1.5 or above 12.4
IU/L	Female	3 – 10	1.7 – 21.5	below 1.7 or above 21.5
IU/L	Male	2 – 8	1.5 – 12.4	below 1.5 or above 12.4

What the evidence says

The bands are laboratory reference intervals (Labcorp): 1.5 to 12.4 IU/L in men, and 1.7 to 21.5 in premenopausal women, which runs from the luteal lower limit to the mid-cycle upper limit. In the follicular phase alone the interval is narrower, about 3.5 to 12.5. For men, the optimal band ends at 8 IU/L, close to the 7.6 above which urology guidance suspects impaired sperm production in men being investigated for infertility. For women the optimal band of 3 to 10 IU/L is a functional target: a day-3 FSH above 10 is often quoted, but the reproductive-medicine society gives no cut-off and women above 10 conceived at similar rates in the cohort it cites. FSH varies across the cycle and rises substantially after menopause (generally above 25 to 40 IU/L), so interpret it with cycle day and menopausal status. These ranges are informative, not diagnostic.

For women: These ranges are informative, not diagnostic, and reflect a follicular-phase reference for women in their reproductive years (pre-menopausal). FSH varies across the menstrual cycle and rises substantially after menopause, so interpret it alongside your cycle day and menopausal status.

Menstrual cycle: Female range is a follicular-phase reference; FSH rises substantially after menopause.

Sources

Follicle-stimulating Hormone (FSH) (test 004309) — Labcorp, 2026 · Laboratory / reference-interval sourceAdult men 1.5 to 12.4 mIU/mL. Women: follicular 3.5 to 12.5, ovulatory 4.7 to 21.5, luteal 1.7 to 7.7, postmenopausal 25.8 to 134.8. Sera's male band of 1.5 to 12 matches; the female band of 1.5 to 20 is close to the luteal lower and ovulatory upper limits.
Follicle-Stimulating Hormone (FSH), Serum — Mayo Clinic Laboratories, 2026 · Laboratory / reference-interval sourceMen over 18: 1.2 to 15.8 IU/L. Premenopausal women: follicular 2.9 to 14.6, midcycle 4.7 to 23.2, luteal 1.4 to 8.9; postmenopausal 16.0 to 157.0. Confirms the same pattern with slightly wider limits.
Diagnosis and Treatment of Infertility in Men: AUA/ASRM Guideline — American Urological Association / American Society for Reproductive Medicine, 2020 · Clinical guidelineIn men with azoospermia, FSH above 7.6 IU/L suggests spermatogenic failure and FSH below it suggests obstruction. Supports an optimal upper edge of 7.6 in men, though the figure comes from infertile men only. Published 2020, amended 2024.
Testing and interpreting measures of ovarian reserve: a committee opinion — Practice Committee of the American Society for Reproductive Medicine — Fertility and Sterility, 2020 · Professional societyGives no diagnostic FSH cut-off. It cites a cohort in which women with FSH above 10 IU/L had similar cumulative pregnancy rates, so 10 is a study criterion, not a threshold for a worse outcome.

What FSH (Follicle-Stimulating Hormone) measures

A pituitary hormone that helps control the reproductive system.

Helps assess fertility and irregular periods, and can show whether someone is approaching or in menopause.

Related hormone health markers

See FSH in the full list of biomarker ranges

This page is a reference for practitioners, not medical advice. Sera's bands are practitioner targets for structured review, not diagnostic thresholds, and Sera does not diagnose or recommend treatment. Read a result alongside the interval printed by the issuing laboratory and the client's history and symptoms. Range set: Sera Production, version 1.0, last reviewed November 9, 2026.