Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal activity: estrone, estradiol, and estriol. Estradiol, an estrane, is the most potent and prevalent. Another estrogen called estetrol is produced only during pregnancy. Estrogens are synthesized in all vertebrates and some insects. Their presence in both vertebrates and insects suggests that estrogenic sex hormones have an ancient evolutionary history. Quantitatively, estrogens circulate at lower levels than androgens in both men and women. While estrogen levels are significantly lower in males than in females, estrogens nevertheless have important physiological roles in males. Like all steroid hormones, estrogens readily diffuse across the cell membrane.

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Estrogen May Offer Protection Against Delirium

Estrogen may offer protection against delirium

Women with elevated breast cancer risk could see mortality benefit from estrogen-blocking drugs

Study in mice suggests that expression of estrogen-related gene can impact post-menopausal breast cancer risk and prevention strategies

For women, greater exposure to estrogen in life may protect brain regions that are vulnerable to Alzheimer’s

An estrogen receptor that promotes cancer also causes drug resistance

Targeting drug-resistant breast cancer with estrogen

Estrogen status - not sex - protects against heightened fear recall

Estrogen status - not sex - protects against heightened fear recall

Is Estrogen Deficiency Really a Thing?

Polymerized estrogen provides neuroprotection in preclinical testing

Oncotarget: Estrogen receptor α polymorphism is associated with dementia