Estrogen is a primary female sex hormone that plays a crucial role in the reproductive system, menstrual cycle, and overall health. It’s produced mainly in the ovaries, with smaller amounts made in fat tissue and the adrenal glands.
What Estrogen Does:
Estrogen regulates the menstrual cycle, supports bone density, influences mood and cognitive function, and maintains healthy skin and hair. It works together with progesterone to prepare the uterus for potential pregnancy each month.
Types of Estrogen:
The body produces three main types: estradiol (E2) – the most potent form during reproductive years, estriol (E3) – increases during pregnancy, and estrone (E1) – the primary estrogen after menopause.
When Estrogen Changes:
Levels fluctuate naturally throughout the menstrual cycle, rising in the first half (follicular phase) and dropping before menstruation. Estrogen declines significantly during perimenopause and menopause, which can cause symptoms like hot flashes, mood changes, and vaginal dryness.

