Your Body's Hormones Hormones are substances that control when
and how certain organs work. They are made by glands in the
body, but also can be made in a lab. Androgens, so-called male
hormones, are made by the ovaries (two glands on either side of
the uterus) in women and by the testes in men. In women,
androgens are used by the ovaries to make estrogen, the so-
called female hormone. The ovaries make estrogen from puberty
until menopause. In women, the hormone estrogen plays a key role
in the reproductive system. Estrogen also affects a woman's
bones and the health of her heart and blood vessels. Women can
take hormones to relieve symptoms of menopause. When a woman
chooses to take hormone therapy, her options depend on whether
she has had her uterus removed. A woman who has had her uterus
removed can take just estrogen. This is because using estrogen
alone causes the lining of the uterus to grow and increases the
risk of endometrial cancer. To reduce this risk it is recommend
that you use a combination of