What are estrogen and progesterone and what do they do?

Let’s start with estrogen. Women actually have three different hormones that perform the functions we attribute to estrogen - estrone, estradiol, and estriol. While more than 90 percent of estrogen is made in the ovaries, smaller quantities are produced by the adrenal glands, liver, kidneys, and women’s body fat.5 Estrogen is necessary for the normal development and growth of the breasts and childbearing organs, including the ovaries and the uterus. It helps control a woman’s menstrual cycle and is essential for reproduction. Estrogen also helps maintain a healthy heart and bones.5 Progesterone, also produced in the ovaries, is the reproductive hormone most closely associated with pregnancy. Under the guidance of progesterone, an egg leaves one of the ovaries and travels to the uterus through the fallopian tubes. Progesterone also builds up a thick cushiony lining on the wall of the uterus. If the released egg is fertilized, it attaches to this cushiony wall, using the extra blood ...  more