In a study of 29 women with frequent, daily hot flashes, researchers found that those who received acupuncture began to have fewer and less severe symptoms during the night.

As nighttime hot flashes improved, so did the quality of the women's sleep, the researchers report in the journal Fertility & Sterility.

Hot flashes are a common part of menopause, and women who get them often have difficulty getting a good night's sleep. Hormone replacement therapy is effective at quelling hot flashes, but given the risks of the therapy -- including increased risks of heart disease and breast cancer -- many women are interested in alternative treatments.

The new findings offer preliminary evidence that acupuncture works, but it's too early to recommend the procedure for hot flashes, senior study author Dr. Rachel Manber told Reuters Health.

"Large replication studies are necessary before we move from bench to bed," said Manber, an associate professor of psychiatry at Stanford University School of Medicine in California.

Recent medical research has found that acupuncture may work by altering signals among nerve cells or by affecting the release of various chemicals of the central nervous system. There's also some evidence that acupuncture affects hormones related to both sleep and menopause.

However, for now, the mechanism by which acupuncture might affect hot flashes is not completely understood, Manber said.

For their study, she and her colleagues randomly assigned 29 women to receive seven weeks of acupuncture or a "sham" version of the procedure. In the latter case, acupuncturists used flat-tipped needles that did not pierce the skin, placing them on areas of the skin not considered to be acupuncture points. The patients could not see that the needles weren't piercing their skin.

By the end of treatment, women who'd been getting the real acupuncture sessions reported a greater reduction in the severity of their nighttime hot flashes than those in the comparison group.

Both groups said their hot flashes had become less frequent, the researchers found, and as hot flash symptoms improved, so did the women's sleep quality.

The sleep improvements were seen in both groups, and acupuncture itself did not seem to have a special effect on sleep. However, Manber pointed out, the acupuncture points used in the study were chosen because they target hot flash symptoms, according to traditional medicine. So the therapy was not designed to directly address sleep problems, she said.

SOURCE: Fertility & Sterility, September 2006.