Estrogen is a hormone which plays a major role in the development of female sexual characteristics, in the regulation of the menstrual cycle and in pregnancy. But estrogen is also present in the male body.
It’s released by the ovaries. It plays a major role in the physical changes during puberty, like the growth of the womb and vagina, the maturing of the external female genitals and breast growth. Estrogen helps to keep the vagina lubricated and supple and plays a role in the production of cervical mucous (which influences the life span of sperm entering the vagina). It also stops the growth of bone and muscle, which accounts for the smaller size of girls as compared with guys. Too much estrogen can inhibit sexual desire.
Estrogen regulates bone density and triggers the production of other hormones.
It is unclear which role estrogen plays in the male body. The increase of estrogen during guys’ teens often causes gynaecomastia.
A few well known estrogens are estrone, estradiol and estriol. Synthetic forms of these hormones are used in the contraceptive pill and in hormone replacement therapy, used to treat the complaints of women in menopause.