ABSTRACT 

Gynecologists view estrogen and progesterone hormone replacement therapy as key for any menopausal woman who wants to remain in her prime. But testosterone, the hormone that fuels sexual desire, is still considered a deviant treatment. 

“The women who come to us with sexual complaints are not the ones who have always had a low sex drive.”  

At a time when many baby boomers are broaching the topic waning sexuality with their physicians, the work of Phillip Sarrel, professor of Obstetrics and Gynecology at Yale University School of Medicine, is compelling. 

Sarrel champions the belief that some menopausal women need testosterone supplements as well as conventional hormone replacement therapy to restore their sexual vigor. “Aside from its role as sexual elixir, testosterone may improve concentration, lift depression, and restore the overall sense of wellbeing most women enjoy until they reach perimenopause,” Dr. Sarrel said, in a recent speech at the 55 th Annual Meeting of the American Society of Reproductive Medicine, in Toronto , Canada . 

“The women who come to us with sexual complaints are not the ones who have always had a low sex drive,” he told colleagues. “They're the ones who have had a high level of desire and want it back. Not to respond to these women is not respond to their quality of life.”  

Steroid Starvation 

He said most gynecologists don't even ask menopausal patients about their sex lives. If they were to ask, they would find these women are living with vaginal dryness, diminishing clitoral sensitivity, difficulty reaching orgasm, infrequent intercourse, and a dysfunctional partner. 

Masters and Johnson, pioneering sexologists of the 1950s, observed the same thing, Sarrel said. They called this condition “steroid starvation” and recommended estrogen to restore vaginal lubrication and sexual function. 

The sexologists were right about estrogen's role in keeping the vagina lubricated. Estrogen also helps to prevent atrophy (shrinkage) of the vaginal lining, which would otherwise occur after menopause, making intercourse painful.  

Elixir and Estrogen Booster  

As crucial as estrogen is, however, it can not replace testosterone as the igniter of both sexual fantasy and function. Even worse, estrogen supplements “tie up” testosterone, so that less is “free” (bioavailable) to work on tissues. Therefore, even a woman who was not lacking in testosterone before she started hormone replacement therapy may become deficient during the course of therapy.  

A study Sarrel published in the Journal of Reproductive Medicine a year ago demonstrates testosterone's dual role. He shows that in addition to improving sexual function, testosterone raises circulating levels of free estrogen in the bloodstream.  

For the purposes of this study, the Yale gynecologist enlisted 20 volunteers who were dissatisfied with hormone replacement therapy because their sex lives were deteriorating. He gave half of the group conventional hormone replacement (either estrogen alone or a combination of estrogen and progesterone) and added testosterone for the other half. 

The women taking testosterone reported “significant increases in sexual sensation and desire and more frequent intercourse after 4 weeks and again at 8 weeks after starting therapy.”  

Sexual function improved. This occurred along with the increase in “free estrogen” from baseline. Interestingly, this occurred even though these same “free” estrogen levels were lower than those measured in the same women during their previous estrogen therapy. Although some trials of testosterone have not found any benefit, a number of other trials have also found testosterone enhances sexual activity, drive, and enjoyment, Sarrel said. 

Here's why women on estrogen might especially need testosterone: Most of a woman's natural testosterone supply is already “bound” to a protein called sex hormone binding globulin, or SHBG. Only about 1% is bioavailable to act on tissues. Estrogen given alone triggers the production of more SHBG, which then binds up more testosterone. 

The SHBG phenomenon explains why women taking estrogen often suffer a relapse in menopausal symptoms, said Alan Altman, assistant professor of obstetrics and gynecology at Harvard Medical School, in an aside after the conference. 

This means that the depression, the fatigue, the headaches, the hot flashes, the racing heart or sleepless nights that may have been part of the menopausal experience return.  

Doctors Add Estrogen Needlessly 

At this point, doctors often mistakenly decide a woman needs even more estrogen, Altman said. In reality, the additional dose will do nothing more than increase side effects and raise the risk of breast cancer, making patients more apt to discontinue their medicine. 

A woman” who wants more bang for the buck” with testosterone may take Estratest (esterified estrogens and methyltestosterone)—a combination of estrogen and testosterone that comes in pill form. Or if she suffers from a lack of sexual sensation, she might opt to rub testosterone cream directly on her clitoris, Altman said. 

Perhaps because some trials in the past have not found a benefit to testosterone, interestingly, Estratest is not approved by the Federal Drug Administration to treat sexual dysfunction. There is no pill on the market for this indication in woman although several testosterone patches exist for men. Estratest is officially approved for hot flashes that don't respond to conventional hormone replacement therapy.

Good for the Heart 

Importantly, Sarrel and the others report or sate that testosterone does not compromise the perhaps beneficial effects estrogen has on the heart; if anything, it augments them. This is important, because one of estrogen's biggest selling points is that it is possible that it slashes the risk of heart attack by up to 50%. 

In a study published in Fertility and Sterility , Sarrel found that testosterone did not constrict blood flow to either the fingertips or to the vagina. In fact, blood flow to the fingertips increased in those women taking testosterone compared to those in the estrogen-progesterone group. 

Scientists examining monkey, dog, and rabbit arteries have also found testosterone relaxes blood vessels, so that blood can be pumped to the heart more easily, Sarrel noted. 

One caveat though: Testosterone decreases HDL (high-density lipoprotein) cholesterol (the good kind) by 10%, so those with low levels of HDL should think twice before taking it. 

**Lynn Shapiro is a medical reporter who lives in New York City . She writes frequently on such topics as psychiatry, reproductive and menopausal medicine, and biotechnology. 

**Reviewed for medical accuracy by a faculty physician, Beth Israel Deaconess Medical Center (BIDMC) and Harvard Medical School . BIDMC does not endorse any products or services advertised on this Web site.