A new statement suggesting that hormone replacement therapy may be the right treatment for women entering menopause has reignited the debate over HRT and challenged a high profile study in 2002 that caused millions of women to abandon the therapy.
"Hormone replacement therapy remains the first-line and most effective treatment for menopausal symptoms," reads the statement, issued by the International Menopause Society today at a conference in Madrid.
The IMS says it reviewed dozens of studies on HRT and concluded the original study was flawed.
Many doctors, including Salim Yusuf, a professor of medicine at McMaster University in Ontario, reacted angrily to the statement.
"I can only conclude that the statement … is highly inaccurate, selects mainly poor quality analyses to support its conclusions and is therefore not only misleading but also dangerous to the health of women worldwide," he told ABC News.
Hanging in the balance are millions of women suffering from postmenopausal symptoms, many of whom are unsure whether to continue HRT, restart a therapy they stopped or begin to take it as they enter menopause.
HRT involves women receiving doses of estrogen, sometimes supplemented by progestin, in order to relieve unpleasant symptoms of menopause.
In 2002, researchers cut short the Women's Health Initiative study of HRT, citing concerns over heart problems and strokes in women in the study who received the treatment.
But while some supported the decision to halt the study, which led many women to stop their HRT regimens, many doctors felt the recommendations went too far, discouraging women they felt should be taking the treatment.
"I think this document is trying to moderate the craziness that came out on the public side of the original recommendations," said Dr. Tom Felger, a clinical assistant professor of family medicine at the Indiana University School of Medicine. "For symptomatic menopausal women, HRT is very effective and safe. The issue was the forever use of it without symptoms."
Other physicians agreed with the IMS, saying it will help women who are too scared to take HRT, but they feel should be on the treatment.
"I applaud the new statement and agree with it completely," said Dr. Donna Shoupe, an OB/GYN at the Keck School of Medicine at USC.
"I will quote it to patients and use it to help them get over the big scare that was placed on estrogen therapy," she said.
Dr. JoAnn Manson, who was one of the principal investigators on the original study that led many to stop HRT, says that the therapy should only be used exceedingly sparingly.
"The only clear indication for systemic hormone therapy is moderate-to-severe hot flashes or nights sweats -- severe enough to interfere with sleep or impair quality of life," said Manson.
But today's IMS statement says doctors may have overreacted to the 2002 study.
"Despite massive, good-quality clinical outcome data on efficacy and safety when HRT is begun for symptoms in the early postmenopausal, many physicians and lay people believe that hormones are risky and undesired even in the most appropriate case scenarios," the IMS said.
Manson acknowledged that some newer HRT studies have been encouraging.
"Recent evidence has been reassuring that, for recently menopausal women who are symptomatic, the benefits of hormone therapy are likely to outweigh the risks … however, low doses should be used for the shortest time necessary, usually less than four to five years," Manson said.
But other doctors remain skeptical of the IMS statement supporting the treatment.
"Good, blinded data do not support an improvement in quality of [life] in the average postmenopausal woman," said Yusuf.