From the Guidelines
During menopause, FSH levels increase more significantly than LH levels, with FSH rising earlier and more dramatically, often reaching levels 10-15 times higher than premenopausal values, while LH increases to a lesser extent, typically 3-5 times premenopausal levels 1. The difference in the levels of Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH) during menopause is attributed to the decline in ovarian function and the subsequent reduction in negative feedback on the pituitary gland.
- FSH levels begin to increase during perimenopause as ovarian follicles become less responsive to hormonal stimulation.
- The marked elevation of FSH occurs because declining estrogen and inhibin B from aging follicles reduces negative feedback on the pituitary gland.
- LH also increases during menopause but generally shows a less pronounced rise.
- The FSH:LH ratio often increases during the menopausal transition, which differs from the relatively balanced ratio seen in reproductive years. These hormonal changes reflect the body's attempt to stimulate follicular development as ovarian function declines.
- Clinically, an FSH level consistently above 30-40 IU/L in a woman with menopausal symptoms is considered diagnostic of menopause, while LH measurements are less commonly used for diagnosis. The provided studies do not directly address the difference between FSH and LH during menopause, but they discuss menopausal hormone therapy and its effects on cardiovascular health 1. However, the information on FSH and LH levels during menopause is based on general medical knowledge and is supported by the fact that FSH levels are often used as a diagnostic marker for menopause.
From the FDA Drug Label
Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and follicle stimulating hormone (FSH), through a negative feedback mechanism. Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.
The main difference between Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH) during menopause is not explicitly stated in terms of their distinct roles or differences. However, it is mentioned that both hormones are elevated in postmenopausal women and are reduced by estrogens through a negative feedback mechanism 2, 2.
- Key Points:
- Both FSH and LH are gonadotropins.
- Their levels are elevated in postmenopausal women.
- Estrogens reduce the levels of FSH and LH through a negative feedback mechanism.
From the Research
Hormonal Changes During Menopause
The menopausal transition is characterized by significant hormonal changes, including alterations in Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH) levels.
- FSH levels increase during the menopausal transition, with a marked decline in ovarian follicle numbers being a primary factor contributing to this increase 3.
- In contrast, LH levels also increase, but the patterns of FSH and LH elevation can vary widely among individuals and over time 4.
FSH and LH Patterns
Studies have identified distinct patterns of FSH and LH elevation during the menopausal transition, including:
- Postmenopausal levels of FSH and LH in association with high estrogen levels 4
- Elevation of LH (but not FSH) into the postmenopausal range 4
- Elevation of FSH (but not LH) into the postmenopausal range 4
- These patterns are not typically seen in premenopausal women and can indicate the approach of menopause 4.
Postmenopausal Hormone Levels
In the postmenopause, FSH levels are markedly raised, while estrogen levels are low, and inhibin B and anti-Mullerian hormone (AMH) are undetectable 3.
- The basal levels of FSH tend to increase with age, with a maximum in the 3rd age group and a decline thereafter 5.
- LH cumulative responses after LH-RH administration are highest in younger postmenopausal women and decline in subsequent age groups 5.
Clinical Implications
The increase in FSH levels during menopause has been linked to various menopause-related conditions, including psychiatric morbidities 6.
- However, FSH has limited utility in distinguishing among women in different reproductive stages due to considerable overlap in FSH distributions among stages 7.