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How does negative feedback regulate estrogen and progesterone levels?

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Diagram of the menstrual cycle showing hormone levels, follicle development, and endometrial changes across 28 days. It highlights menstruation, ovulation, and the follicular and luteal phases, with labeled curves for estrogen, progesterone, FSH, and LH. — menstruation Cyclical changes during a woman's normal ovulatory menstrual cycle.

Negative feedback is a critical regulatory mechanism in the menstrual cycle that maintains hormonal balance between the hypothalamus, the pituitary gland, and the ovaries.12

This process functions as follows:

Estrogen Feedback: As ovarian follicles mature, they secrete estrogen. Rising levels of estrogen exert negative feedback on the pituitary gland to inhibit the further output of follicle-stimulating hormone (FSH).12
Progesterone Feedback: Following ovulation, the corpus luteum produces large quantities of progesterone. Progesterone acts to inhibit the further output of luteinizing hormone (LH) from the pituitary.12

By inhibiting these gonadotropic hormones, the body prevents the development of additional follicles and further ovulation during the luteal phase, ensuring that the reproductive system remains focused on the potential for pregnancy. This feedback loop is essential for the stability of the cycle, and its disruption—such as through the use of birth control pills containing synthetic hormones—can effectively suppress ovulation.12