Why Estrogen Balance is Important Estrogen is the name of the class of hormones related to the reproductive cycle.  It includes the three main estrogens called estrone, estradiol, and estriol.  Each of these plays a role in the hormonal balance in women. In healthy premenopausal women, estrogen is made from progesterone and/or from androgens within the ovary's cells. Estrogen is responsible for changes in young women at puberty and gives adult women their shapely curves. During childbearing years, estrogen rises during the first half of the menstrual cycle in preparation for pregnancy. Elevated estrogen causes water retention and weight gain, and too much estrogen can lead to excess fat…