Estradiol is a female sex hormone and a form of estrogen. It is found in both sexes but predominantly in women due to the ovaries while small amounts are produced in the testicles and adrenal glands. While testosterone can convert into estradiol, estradiol cannot be converted back into testosterone.
It is responsible for inducing breasts (see gynecomastia for men), curves, wide hips, among many other female secondary sex characteristics.
