Estradiol (E2) is the main estrogen in reproductive-age people, regulating the menstrual cycle and promoting follicle maturation and ovulation. It drives female secondary sexual characteristics (breast development), maintains bone density, influences lipid metabolism and cardiovascular health, supports vaginal and urogenital tissues and lubrication, and affects mood and cognitive function. In both sexes it helps bone maintenance and hormonal balance.

Normal estradiol (E2) levels vary with menstrual phase. Typical ranges: follicular 20–150 pg/mL, mid‑cycle (ovulatory) peak 150–750 pg/mL, luteal 30–450 pg/mL. Postmenopausal values are much lower, usually <20–30 pg/mL. Exact reference ranges depend on the laboratory and assay; discuss your results with a clinician.

High estradiol (E2) can cause menstrual irregularities, heavy bleeding, breast tenderness, bloating, mood swings, and fertility problems in women; in men, it may cause gynecomastia, low libido, erectile dysfunction, and reduced sperm production. Chronically high E2 raises risks of blood clots, stroke, endometrial hyperplasia/cancer, and liver issues. Evaluation by a clinician is recommended.

A good estradiol (E2) for getting pregnant is a rising level that reaches roughly 200–600 pg/mL (≈730–2,200 pmol/L) before ovulation, which suggests adequate follicle maturity and boosts conception chances. Lower E2 may indicate poor follicular growth; very high E2 can signal multiple follicles or OHSS risk. Targets vary by lab, treatment and individual—discuss your results with your fertility clinician.

Low estradiol (E2) commonly causes menstrual irregularities or absent periods, hot flashes, night sweats, vaginal dryness, painful intercourse, low libido, mood swings, fatigue and difficulty concentrating. Long-term deficiency accelerates bone loss, raising osteoporosis and fracture risk, and can unfavorably affect cholesterol and cardiovascular health. It also impairs fertility and may require evaluation and treatment to address symptoms and prevent complications.

Estrogen is often called the “beauty hormone.” Produced mainly by the ovaries, it helps preserve skin thickness, elasticity and hydration by supporting collagen production and healthy blood flow. Estrogen also influences hair growth, nail strength and fat distribution; levels decline with age and after menopause, contributing to thinner, drier skin and hair changes.