Estradiol (E2) is a major form of estrogen, a steroid hormone that plays a crucial role in the regulation of the menstrual cycle and reproductive system in females. It is produced primarily by the ovaries, with minor contributions from the adrenal glands and, during pregnancy, the placenta. Estradiol is essential for the development and maintenance of female reproductive tissues, including the endometrium, fallopian tubes, and vaginal lining.
