Estrogen is a female hormone that is secreted by the ovaries beginning at the onset of puberty. Estrogen circulates throughout the body in the blood, and sends signals to a number of organs such as the breasts and uterus. When women enter menopause, their ovaries stop secreting estrogen, which severely diminishes estrogen in the blood, and leads to unpleasant side effects as the body adjusts to new hormone levels. Some women may supplement estrogen levels by taking hormone replacement therapy (HRT) to alleviate the symptoms of menopause. HRT comes with the risk of unpleasant or harmful side effects within the body.
Risk of Uterine Cancer
Since estrogen plays a role in proliferation and growth of uterine cells, increased estrogen levels due to HRT can increase a woman's risk of developing uterine cancer. According to the Washington University School of Medicine, women who take estrogen-only supplements after menopause have a much higher risk of uterine cancer, as the estrogen may help turn normal uterine cells into cancerous ones. To alleviate this risk, women should consider HRT that involves taking both estrogen and progesterone.
Breast Pain
At the onset of puberty, estrogen levels increase dramatically, and this increase signals for the growth and proliferation of breast cells. The breasts retain sensitivity to estrogen after puberty and throughout life, and exposure to estrogen during the menstrual cycle triggers subtle waves of growth of breast tissue. If estrogen is taken as a supplement in hormone replacement therapy, it can lead to swelling and growth of the breasts. In some cases, this leads to breast pain, as the breasts become engorged.
The University of Rochester recommends lowering the dose of estrogen in patients who experience breast pain during hormone therapy. Using over-the-counter medications like Motrin or Aleve may also ease breast pain.
Gallstones
Women taking estrogen supplements are also at an increased risk for gallstone formation. Gallstones develop when chemicals within the bile duct begin to aggregate and form salt crystals, which can block the bile ducts, causing pain, as well as other side effects. According to the University of Maryland Medical Center, estrogen treatment increases the risk of gallstones because estrogen signals the liver to transfer more cholesterol from the blood into the bile duct. The increased cholesterol leads to the accumulation of bile salts, and may eventually lead to gallstones.
The University of Maryland Medical Center reports that women receiving estrogen therapy may double or triple their risk of developing gallstones. Using a patch or gel to supplement estrogen may slightly reduce the risk of gallstones over taking a pill. Once gallstones have formed, treatment may require surgery to remove the gallbladder.
