It is also important in the development and maintenance of female reproductive tissues such as the mammary glands, uterus and vagina during puberty, adulthood and pregnancy.

[8][9] Estradiol is produced within the follicles of the ovaries and in other tissues including the testicles, the adrenal glands, fat, liver, the breasts, and the brain.

[11][12] These changes are initiated at the time of puberty, most are enhanced during the reproductive years, and become less pronounced with declining estradiol support after menopause.

Thus, estradiol produces breast development, and is responsible for changes in the body shape, affecting bones, joints, and fat deposition.

[11][12] In females, estradiol induces breast development, widening of the hips, a feminine fat distribution (with fat deposited particularly in the breasts, hips, thighs, and buttocks), and maturation of the vagina and vulva, whereas it mediates the pubertal growth spurt (indirectly via increased growth hormone secretion)[13] and epiphyseal closure (thereby limiting final height) in both sexes.

During the menstrual cycle, estradiol produced by the growing follicles triggers, via a positive feedback system, the hypothalamic-pituitary events that lead to the luteinizing hormone surge, inducing ovulation.

[23] Women past menopause experience an accelerated loss of bone mass due to a relative estrogen deficiency.

[25] Hormone replacement therapy consisting of systemic treatment with estrogen alone or in combination with a progestogen, has well-documented and considerable beneficial effects on the skin of postmenopausal women.

[25] In addition, a study has found that topical 2% progesterone cream significantly increases skin elasticity and firmness and observably decreases wrinkles in peri- and postmenopausal women.

[27] The positive and negative feedback loops of the menstrual cycle involve ovarian estradiol as the link to the hypothalamic-pituitary system to regulate gonadotropins.

[28] Estrogen is considered to play a significant role in women's mental health, with links suggested between the hormone level, mood and well-being.

Sudden drops or fluctuations in, or long periods of sustained low levels of estrogen may be correlated with significant mood-lowering.

Clinical recovery from depression postpartum, perimenopause, and postmenopause was shown to be effective after levels of estrogen were stabilized and/or restored.

There is also evidence the programming of adult male sexual behavior in many vertebrates is largely dependent on estradiol produced during prenatal life and early infancy.

[32] It is not yet known whether this process plays a significant role in human sexual behavior, although evidence from other mammals tends to indicate a connection.

[40] During pregnancy, high levels of estrogens, namely estradiol, increase coagulation and the risk of venous thromboembolism.

The result of ER activation is a modulation of gene transcription and expression in ER-expressing cells, which is the predominant mechanism by which estradiol mediates its biological effects in the body.

[42] Unlike the case of the ER, GPER appears to be selective for estradiol, and shows very low affinities for other endogenous estrogens, such as estrone and estriol.

Once bound E2, ERs dissociate from the molecular chaperone complexes and become competent to dimerize, migrate to nucleus, and to bind to specific DNA sequences (estrogen response element, ERE), allowing for gene transcription which can take place over hours and days.

[62] Estradiol levels are minimal and according to most laboratories range from 20 to 80 pg/mL during the early to mid follicular phase (or the first week of the menstrual cycle, also known as menses).

[62] Circulating levels are typically between 130 and 200 pg/mL at this time, but in some women may be as high as 300 to 400 pg/mL, and the upper limit of the reference range of some laboratories are even greater (for instance, 750 pg/mL).

[62][64] The mean integrated levels of estradiol during a full menstrual cycle have variously been reported by different sources as 80, 120, and 150 pg/mL.

[69] During the reproductive years of human females, levels of estradiol are somewhat higher than that of estrone, except during the early follicular phase of the menstrual cycle; thus, estradiol may be considered the predominant estrogen during human female reproductive years in terms of absolute serum levels and estrogenic activity.

[citation needed] The estradiol produced by male humans, from testosterone, is present at serum levels roughly comparable to those of postmenopausal women (14–55 versus <35 pg/mL, respectively).

Overall, when the division of a given amount of money was framed as either fair or unfair in a modified version of the ultimatum game, estradiol increased the acceptance rate of fair-framed proposals among men and decreased it among women.

However, among the placebo-group "the mere belief of receiving estradiol treatment significantly increased the acceptance of unfair-framed offers in both sexes", indicating that so-called "environmental" factors played a role in organising the responses towards these presentations of the ultimatum game.

[87][88] In 1926, Parkes and Bellerby coined the term estrin to describe the hormone on the basis of it inducing estrus in animals.

[85] Estradiol was subsequently isolated and purified from sow ovaries by Doisy in 1935, with its chemical structure determined simultaneously,[92] and was referred to variously as dihydrotheelin, dihydrofolliculin, dihydrofollicular hormone, and dihydroxyestrin.

[85][93][94] In 1935, the name estradiol and the term estrogen were formally established by the Sex Hormone Committee of the Health Organization of the League of Nations; this followed the names estrone (which was initially called theelin, progynon, folliculin, and ketohydroxyestrin) and estriol (initially called theelol and trihydroxyestrin) having been established in 1932 at the first meeting of the International Conference on the Standardization of Sex Hormones in London.

οἶστρος (oistros, literally meaning "verve or inspiration"),[96] which refers to the estrane steroid ring system, and -diol, a chemical term and suffix indicating that the compound is a type of alcohol bearing two hydroxyl groups.