WASHINGTON -- A drug commonly used to treat circulatory disorders may prove to be an effective new therapy for infertility caused by endometriosis, an often painful condition suffered by millions of women worldwide, researchers said yesterday.
In a study directed by Dr. Alex Steinleitner of Mount Sinai Medical Center in Miami, researchers induced endometriosis in hamsters. All hamsters subsequently given the drug pentoxifylline became fertile, and none of the untreated animals became pregnant, said Dr. Steinleitner, who is co-director of Mount Sinai's in-vitro fertilization program.
The findings were presented at a meeting here of the American Fertility Society.
Dr. Steinleitner said that he expected to begin studies in women shortly. If the results in humans parallel those in animals, he predicted that the drug would become "a revolutionary treatment" for infertility caused by the disease.
Endometriosis results when normal endometrial tissue -- the lining of the uterus -- grows in abnormal locations, such as the ovaries, Fallopian tubes, outer surface of the uterus, bowel and abdominal cavity. It often afflicts women in their 30s and 40s who have delayed childbearing.
Dr. Steinleitner said that up to 40 percent of women who are infertile suffer from endometriosis.
The only current treatments for the condition are surgery or doses of danazol, a male hormone that produces side effects similar to those associated with menopause.
Also, both of those treatments frequently cause only a temporary disappearance of endometriosis and do not always have an impact on infertility.
Dr. Alan Decherney, an expert on endometriosis and professor of obstetrics and gynecology at Yale University, described the drug as a unique approach and said the findings offer significant promise. But he cautioned that infertility is caused by many factors. "Many women have endometriosis and are perfectly fertile, so there's more to it than meets the eye," he said.
The researchers emphasized that the animal results must be duplicated in human studies before the drug is used to treat infertility associated with endometriosis.
Dr. Steinleitner said the only known side effect of the drug is that it causes "mild" stomach upsets in up to 5 percent of those who take it for its currently approved uses.