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How do ovarian follicles produce estrogens?
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Animal reproductive system
The process of sexual reproduction and several forms of parthenogenesis.
Ovarian follicles produce estrogens through a collaborative process involving two distinct cell layers: the theca cells and the granulosa cells.1
The synthesis begins with cholesterol, which serves as the precursor for all ovarian steroid hormones. The process generally follows these steps:2
- Androgen Production: Theca cells, which form an enclosing sheath around the follicle, primarily produce androgens, such as androstenedione and testosterone.12
- Conversion to Estrogens: These androgens diffuse into the adjacent granulosa cells. Within these cells, the androgens are converted into estrogens—specifically estradiol and estrone—through the action of an enzyme called aromatase.12
This production is regulated by gonadotropins, specifically follicle-stimulating hormone and luteinizing hormone, which are secreted by the pituitary gland. Once synthesized, these estrogens are released into the bloodstream to influence the development and function of the female reproductive tract.132