Oestrogen

Estrogen
Drug class
Estradiol, the major estrogen in humans and a widely used medication.
Class identifiers
Use	Contraception, Menopause, hypogonadism, transgender women, prostate cancer, breast cancer, others
ATC code	G03C
Biological target	Estrogen receptors (ERα, ERβ, mERs (e.g., GPER, others))
External links
MeSH	D004967

Estrogen (American English) or oestrogen (British English) is the primary female sex hormone as well as a medication. It is responsible for the development and regulation of the female reproductive system and secondary sex characteristics. Estrogen may also refer to any substance, natural or synthetic, that mimics the effects of the natural hormone. The estrane steroid estradiol is the most potent and prevalent endogenous estrogen, although several metabolites of estradiol also have estrogenic hormonal activity. Estrogens are used as medications as part of some oral contraceptives, in hormone replacement therapy for postmenopausal, hypogonadal, and transgender women, and in the treatment of certain hormone-sensitive cancers like prostate cancer and breast cancer. They are one of three types of sex hormones, the others being androgens/anabolic steroids like testosterone and progestogens like progesterone.