About a quarter of U.S. women who stopped taking hormone replacement therapy after it was found to raise the risk of heart disease and some cancers have gone back on it, the American College of Obstetricians and Gynecologists (ACOG) said on Friday.

That is appropriate for women who are having severe symptoms associated with menopause, such as debilitating hot flashes, so long as they take a small dose for the shortest time needed, ACOG said.

The organization also issued new guidelines saying herbal remedies do not do much for women having difficulty with menopause. And it called for more research into whether hormone replacement therapy may be safer for younger women.

In 2002, researchers shocked the medical world and many women when they contradicted common wisdom that hormone replacement therapy not only made women feel better during and after menopause, but that it helped prevent heart disease, cancer and possibly senility.

In fact, hormone replacement therapy raised the risk of stroke, heart attack and some cancers and later research showed it did not prevent Alzheimer’s disease.

But the study, called the Women’s Health Initiative, was done in women well past menopause, with an average age of 65. Doctors were quick to note that hormone replacement therapy could still be valuable and safe for younger women just going through the change of life.

“Approximately 65 percent of women on (hormone replacement therapy) stopped therapy after the (Women’s Health Initiative),” said Dr. Isaac Schiff, chair of the American College of Obstetricians and Gynecologists Task Force on Hormone Therapy.

“Two years later, reports suggest that about 1 in 4 women who stopped (the therapy) went back on it because it still offers the best relief for menopausal symptoms.

“So we’re moving back to an appropriate balance - accepting that (hormone therapy) has risks, but recognizing that it can be appropriate for conditions like hot flashes so long as women are informed about the risks and weigh their decision with their doctor,” he added.

The group’s new guidance also said anti-anxiety drugs known as selective serotonin reuptake inhibitors can help treat hot flashes. But herbal remedies have shown disappointing results.

“Treatment with wild yam extract, black cohosh, or dietary phytoestrogen supplements derived from the isoflavone red clover has no significant effects on vasomotor symptoms,” the guidelines said.

They also called for more study.

“Are the effects of hormones different for the more typical menopausal patient at the average age of 51, or for younger women who have undergone surgical or premature menopause?” asked American College of Obstetricians and Gynecologists adviser Dr. Deborah Smith.