Getty: I Love Images

Getty: I Love Images

For years, researchers have considered estrogen the primary hormone tied to the development and growth of fibroids. The hormone progesterone is often used as a treatment that reduces fibroid-related bleeding, but not the size of fibroids.

A new study, conducted at Stanford University School of Medicine, reports that testosterone also plays a role in the development of fibroids in middle age when women enter perimenopause and hormone levels begin to destabilize.

“Our findings are particularly interesting because testosterone was previously unrecognized as a factor in the development of uterine fibroids,” study co-author Jennifer Lee, M..D, in a statement from the Endocrine Society.

For the study, nearly 1400 women were followed for 13 years. They had their testosterone and estrogen levels checked annually. Those with the highest blood levels of testosterone were 1.3 times more likely to develop uterine fibroids than those with the lowest levels. The risk of developing fibroids was greatest in women who had high levels of both testosterone and estrogen.

Oddly, while women with high levels of estrogen and testosterone where more likely to develop fibroids in the first place, they were less likely to develop them again, later in life, than women with lower levels of the hormones. More than 80 percent of black women and 70 percent of white women have fibroids at some point in life.

The study is helpful because it adds to the information scientists have about what contributes to fibroid growth and development.

Testosterone – The Guy Hormone

Many women consider testosterone, the male sex hormone, to be unimportant to women. In fact, women produce small amounts of the hormone. Abnormally high levels of testosterone in a woman may cause absent menstrual periods, frontal balding, acne, an unusually deep voice or excess body hair.

Even if your levels are perfectly normal, your hormones may fall out of balance during perimenopause — the several year transition toward menopause. “Our research suggests women undergoing the menopausal transition who have higher testosterone levels have an increased risk of developing fibroids, particularly if they also have higher estrogen levels,” said study co-author Jason Wong, from the Stanford University School of Medicine in California.

Lee added that “the research opens up new lines of inquiry regarding how fibroids develop and how they are treated.”

“Given that managing uterine fibroids costs an estimated $34.4 billion in annual medical expenditures nationwide, it is important to identify new ways to better treat this common condition,” she said.

While the study found an association between hormone levels and the risk of uterine fibroids, it did not prove a cause-and-effect relationship.

But, women hoping to avoid the additional risk of developing fibroids dues to unnaturally high levels of testosterone and estrogen during perimenopause can take some precautions. A healthy lifestyle can aid in hormone balance. Avoid high-fat, high-sugar foods, and red meat. Eat a diet rich in fruits and vegetabls and healthy oils, such as the  Mediterranean Diet or DASH Diet, and maintain a healthy weight. Click here, to learn more about beating fibroids.