The actions of estrogen are mediated by the estrogen receptor (ER), a dimeric nuclear protein that binds to DNA and controls gene expression. Like other steroid hormones, estrogen enters passively into the cell where it binds to and activates the estrogen receptor.

Estrogen is a sex hormone that’s necessary for maintaining your sexual and reproductive health. Estrogen levels naturally fluctuate during different life stages and your menstrual cycle.

In this article, we look at estrogen in more detail, including how it works, what happens when the levels fluctuate, and medical uses.

In addition to regulating the menstrual cycle, estrogen affects the reproductive tract, the urinary tract, the heart and blood vessels, bones, breasts, skin, hair, mucous membranes, pelvic muscles, and the brain.

Estrogen is a sex hormone that plays a key role in a female’s reproductive health. Learn what estrogen does to the body.

Estrogen, any of a group of hormones that primarily influence the female reproductive tract in its development, maturation, and function. There are three major hormones—estradiol, estrone, and estriol—among the estrogens, and estradiol is the predominant one.

Estrogen is a hormone that plays a role in sexual development, bone health, mood regulation, and more. Find out how fluctuating levels can affect you.

Estrogen levels naturally lower as you age and approach menopause. But low estrogen can also be a sign of a condition or the result of a medical treatment.

Estrogen therapy has several indications, from hormonal contraception to menopause treatment. Estrogen medications are usually taken as pills or transdermal patches, although it is also possible to find estrogen in cream or gel form.

Estrogens are used as part of some oral contraceptives and also in estrogen replacement therapy of post-menopausal women.