Why are so many women in the United States getting hysterectomies? More than 600,000 women each year are undergoing the surgery, making hysterectomies the most common major surgery performed for nonobstetric reasons.

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"In the last decade, there have been questions raised regarding the appropriate use of hysterectomy and specifically whether this procedure might be done a little too frequently," said Dr. Miriam Kuppermann, of the University of California, San Francisco.

Kuppermann and several colleagues studied hysterectomies compared with medical treatments to find out what gave patients a better quality of life at the end of two years. Their findings were published in this week's Journal of the American Medical Association.

The 63 women in the study had abnormal uterine bleeding, defined as more than seven days of flow per month or anemia due to heavy periods, for an average of four years. They were randomly placed in either the hysterectomy or medical treatment groups so that the results would be scientifically reliable.

The researchers found that both hysterectomy and expanded medical treatment were helpful, but hysterectomies generally brought quality-of-life improvements faster than medical treatment -- often after only six months.

"If they choose to have a hysterectomy after one common medical treatment has failed, they can expect excellent improvements in quality of life over two years of follow-up," said Dr. Lee Learman, also of the University of California.

But Learman said that if women don't want to have a hysterectomy and they can stick with expanded treatments with medication for two years, then they can also expect substantial improvement from where they started.

The question may be if women can wait that long. In the end, half of the women in the medical treatment group elected to have a hysterectomy.

"The findings bring really good news for us to share with our patients who have tried one common medical treatment for heavy menstrual bleeding and who aren't happy with the results of that first line treatment," Learman said.