Definition: Estrogen is a hormone secreted primarily by the ovaries, but it is also secreted by the adrenal glands and from fatty tissues. While we often refer to estrogen as a hormone alone, estrogens are actually a group of like hormones, which include estrone, estradiol and estriol. Estrogen affects the body in many ways, but its main duty in the female reproductive system is to signal to the lining of the uterus, the endometrium, to grow. Estrogen is also responsible for the increase in fertile cervical mucus and increased sexual desire that comes just before ovulation.
Also Known As: oestrogens
