Declining ovarian estradiol and inhibin during the menopausal transition raise FSH and LH.

An independent, comprehensive scientific evaluation of the provided clinical question has been conducted. Below is the synthesis of the evidence, indicating that the statement is factual.

Clinical and Physiological Evidence

The transition from premenopause to postmenopause (the menopausal transition, or perimenopause) is characterized by a profound neuroendocrine disruption initiated by the progressive depletion of the ovarian follicular pool.

• Decline of Ovarian Hormones (Estradiol and Inhibin): As the ovarian reserve declines, there is a progressive loss of follicular cohort size and quality. This leads first to a marked decline in inhibin B (secreted primarily by developing follicular cohorts in the early follicular phase) and later to erratic fluctuations and an eventual overall decline in estradiol ($E_2$).
• Impairment of Negative Feedback: In a normally functioning hypothalamic-pituitary-gonadal (HPG) axis, estradiol and inhibins exert negative feedback on the hypothalamus (reducing GnRH pulse frequency) and directly on the anterior pituitary (suppressing gonadotropin synthesis and secretion). Specifically, inhibin B is a selective inhibitor of follicle-stimulating hormone (FSH) synthesis and release. As the levels of these ovarian hormones drop, the negative feedback loop is disrupted, de-repressing the anterior pituitary.
• Elevation of Gonadotropins (FSH and LH): Without the inhibitory feedback of inhibin B, FSH levels rise significantly, often serving as the earliest hormonal marker of reproductive aging (the "monotropic" FSH rise). As the transition progresses and estradiol levels also drop consistently, negative feedback on luteinizing hormone (LH) is likewise diminished, leading to elevated LH levels.

Experimental and Clinical Markers

• STRAW+10 Stages: According to the Stages of Reproductive Aging Workshop (STRAW+10) guidelines, an elevated monophasic FSH level ($>25\text{ mIU/mL}$) measured during the early follicular phase is a key diagnostic marker of late menopausal transition (Stage -1).
• Endocrine Profiles: Clinical studies confirm that FSH rise precedes the rise in LH, primarily due to the early loss of inhibin B, whereas LH remains relatively stable until closer to the final menstrual period (FMP), after which both gonadotropins remain permanently elevated.

In Summary

The claim is physiologically accurate and represents the classical endocrine model of female reproductive aging, where Ovarian Insufficiency $\rightarrow$ Loss of Negative Feedback $\rightarrow$ Compensatory Pituitary Gonadotropin Hypersecretion.