Britannica Sources used in this answer

How do the ovaries function as endocrine glands?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Diagram showing the locations of major human endocrine glands in male and female bodies, including pineal gland, hypothalamus, pituitary gland, parathyroid glands, thyroid gland, thymus, adrenal glands, pancreas, kidneys, testes, and ovaries. — Endocrine system The glands of the human endocrine system.

The ovaries function as essential endocrine glands by secreting steroid hormones directly into the bloodstream to regulate female reproductive processes, sexual development, and other physiological functions.12

Key Hormonal Functions

The ovaries produce several critical hormones that coordinate the menstrual cycle and sustain pregnancy:

Estrogens: Primarily secreted by the ovarian follicles, these hormones stimulate the development of female secondary sex characteristics, promote the maturation of ovarian follicles, and support the maintenance of bone tissue.13
Progesterone: Produced largely by the corpus luteum after ovulation, this hormone prepares the uterine lining (endometrium) for embryo implantation and is vital for maintaining pregnancy.453
Relaxin: This hormone induces the relaxation of pubic ligaments during childbirth to facilitate delivery.3
Inhibin: This substance helps regulate the reproductive cycle by inhibiting the secretion of follicle-stimulating hormone from the pituitary gland.3

Mechanisms of Action

Ovarian endocrine activity is highly dynamic and cyclic. During the follicular phase, gonadotropins from the pituitary gland stimulate follicle growth and estrogen production. Following ovulation, the ruptured follicle transforms into the corpus luteum, shifting the primary hormonal output toward progesterone. Beyond systemic circulation, ovarian hormones also exhibit paracrine function, where they act locally on adjacent tissues to support processes like follicle maturation.4153