Age is a factor for women with heavy menstrual bleeding who undergo a procedure to remove the endometrium, or lining of the womb. The younger they are at the time of the procedure, the more likely they will eventually require a hysterectomy, according to a new report.

Dr. Mindyn K. Longinotti, from Kaiser Permanente Northern California in San Francisco, told Reuters Health, "The main change that has occurred in my counseling of patients after this research is the ability to discuss failure rates of endometrial ablation based on the patient's age." Over the long term, the probability of not needing a hysterectomy is "more likely in women over the age of 45."

Longinotti and colleagues conducted a study to identify what factors predicted that so-called endometrial ablation wouldn't solve the problem of heavy bleeding and that a hysterectomy would be needed eventually.

Among 3681 women who underwent endometrial ablation, 774 (21 percent) subsequently needed a hysterectomy, the investigators report in the medical journal Obstetrics & Gynecology.

Age was the only significant risk factor for subsequent hysterectomy, the researchers found, with women under age 45 being twice as likely to have a hysterectomy as women over 45.

The likelihood of needing a hysterectomy increased with the time after endometrial ablation, and after 8 years the probability was 12 percent for women older than 50 at the time of ablation, 19.8 percent for women aged 45 to 49.9 years, 31 percent for women aged 40 to 44.9 years, and 40.6 percent for women younger than 40 years.

"Additional studies with longer follow-up are necessary to determine whether endometrial ablation is more likely to replace, or merely delay, hysterectomy in women aged younger than 40 years at the time of the procedure," the researchers conclude.