Hormones that help to develop sex organs in men. They also help to keep up sexual function in both women and men. In women, most of them are changed into estrogen by fat and muscle cells. After menopause, when the ovaries no longer make estrogen, this is the main source of estrogen made in the body.
For more information, see Breastcancer.org's Hormonal Transitions page.
Audio contributed by: John Mahoney