what is oestrogen

Oestrogen is a hormone that plays an important role in the normal sexual and reproductive development in women and people of all sexes. It is one of the main female sex hormones, but both females and males produce oestrogen. In the female body, oestrogen is mostly produced by the ovaries and is needed for puberty, breast development, the menstrual cycle, fertility and pregnancy, bone strength, and maintaining normal cholesterol levels. There are three types of oestrogen in females, produced at different phases of life: oestradiol, oestriol, and oestrone. Oestrogen also affects the reproductive tract, the urinary tract, the heart and blood vessels, bones, breasts, skin, hair, mucous membranes, pelvic muscles, and the brain. It is responsible for breast development, the widening of hips, the deposition of fat in certain areas of the body, and the enhancement of pubic and underarm hair growth during puberty. Oestrogen also helps to grow the lining of the womb, vagina, and vulva, promoting the growth and maintenance of the uterine lining during the menstrual cycle. Oestrogen levels naturally fluctuate during the menstrual cycle and decline during menopause.