TUESDAY, Feb. 24 (HealthDay News) -- What has been intuitively obvious to women for eons now has "real" scientific backing.

Women who are waiting for results after a breast biopsy experience abnormalities in the levels of a stress hormone known as cortisol, a fact that might not only be damaging to overall health but might compromise future treatment if, in fact, the results come back positive.

The findings, appearing in the March issue of Radiology, argue for faster relaying of results to patients.

"For a long time, there has been the recognition that women should find out sooner what they have, but there was just not much effort put into it," said Dr. Elvira V. Lang, an associate professor of radiology at Harvard Medical School in Boston and an author of the study. "When women just say they're stressed, there's a tendency to put it aside as psychological. But once you can show there can be adverse effects on the immune system and on what the next steps are, particularly in women who may be diagnosed and women who have future interactions with the health-care system, then this gets a completely different light on it."

"The medical community isn't going to believe this until there's some biochemical data," she added.

"These findings don't surprise me," said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. "It's very stressful, and we try to have biopsies that have as quick a turnaround as possible. We have emergency medical records so patients today are going to get a CAT scan, are going to get off the table, walk off the elevator and see me and get their results immediately."

More than a million breast biopsies are performed in the United States each year, with 80 percent of them turning up clear.

The researchers obtained cortisol samples from the saliva of 126 women, 18 to 86 years old, each day for five days after they had undergone a large-core breast biopsy.

They then compared cortisol levels among women who did not yet know the outcome of the biopsy ("uncertain group"), women who had a diagnosis of cancer ("known malignant group") and women who were relieved to know they did not have cancer ("known benign group").