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Hormone · Also: E2, 17-beta-estradiol

Estradiol

The primary and most potent estrogen produced by the ovaries during the reproductive years.

The primary and most potent estrogen produced by the ovaries during the reproductive years.

Also known as: E2, 17-beta-estradiol

Estradiol (E2) is the main estrogen made by the ovaries before menopause. Its levels fluctuate across the menstrual cycle and fall as ovarian function declines during perimenopause.

Estradiol is the form of estrogen used in many modern menopausal hormone therapy products, available as a transdermal patch, gel, spray, oral tablet, or vaginal preparation.

Related terms

Estrogen

A group of sex hormones (chiefly estradiol, estrone, and estriol) central to female reproductive health.

Estrone

A weaker estrogen that becomes the predominant circulating estrogen after menopause.

Estriol

The weakest of the three main estrogens, produced in large amounts during pregnancy.

Progesterone

A hormone released after ovulation that prepares and protects the uterine lining.

HRT

Treatment that replaces estrogen (with a progestogen if the uterus is present) for menopause symptoms.

Transdermal

Delivery of medication through the skin, as with a patch, gel, or spray.

Source

MedlinePlus: Estrogen Levels Test

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