FSH is secreted by the anterior pituitary under the control of hypothalamic gonadotropin-releasing hormone (GnRH). In both males and females, FSH facilitates the development and maintenance of gonadal tissues. These tissues synthesize and secrete steroid hormones, which regulate FSH concentrations via negative feedback.
At menopause, ovarian function and steroid secretion cease, resulting in elevated FSH due to lack of negative feedback. FSH concentrations are similarly increased in premenopausal women with ovarian failure or incomplete ovarian maturation during puberty. In males, elevated FSH is observed when testes fail to reach functional maturity or in cases of infertility due to primary testicular failure.
≤ –20 °C; avoid repeated freeze–thaw cycles. For short-term storage (≤8 hours), samples may be kept at room temperature (15–30 °C); for up to 48 hours, refrigerate at 2–8 °C.
Hemolyzed or unspun specimens (may yield inaccurate results)
Enhanced chemiluminescence.
| Category | FSH (mIU/mL) |
| Female, mid-follicular phase | 3.85–8.78 |
| Female, mid-cycle peak | 4.54–22.51 |
| Female, mid-luteal phase | 1.79–5.12 |
| Postmenopausal female | 21.5–131 |
| Male | 1.27–19.26 |