follicular stage

biology

Also known as: follicular phase

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July 19, 2026

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The follicular stage is a phase within the menstrual cycle of female mammals, including humans. This stage begins with the enlargement and migration of several follicles from the ovary's cortex. Each follicle contains an immature egg and is lined by cells that multiply to form the zona granulosa. Surrounding these cells, the follicle develops a theca layer.

During this phase, cells within the follicle produce androgens, which are converted into estrogens. These hormones are crucial for female sexual development and regulating the menstrual cycle. The follicular phase typically lasts about two weeks, culminating in the maturation of one or more follicles, known as Graafian follicles, which are then prepared for ovulation. This process is stimulated by follicle-stimulating hormone (FSH) from the pituitary gland.12345

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Follicular development
…cycle, known as the early follicular phase, several follicles enlarge and migrate from the cortex toward the outer surface of the ovary. The cells lining the follicle multiply to form a layer known as the zona granulosa, and a cavity forms within this zone. The stromal and interstitial cells that…
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…cycle, known as the early follicular phase, several follicles enlarge and migrate from the cortex toward the outer surface of the ovary. The cells lining the follicle multiply to form a layer known as the zona granulosa, and a cavity forms within this zone. The stromal and interstitial cells that…
Read More