Prognosis: A Breast Cancer Reassurance

Many women of childbearing age who develop breast cancer worry that the stresses and hormonal changes of pregnancy will be dangerous. But a new study released yesterday in the journal Cancer found that becoming pregnant after a diagnosis does not raise the risk of dying.

The study, led by Dr. Beth A. Mueller of the Fred Hutchinson Cancer Research Center in Seattle, said the issue was particularly pertinent because the number of women younger than 45 in whom breast cancer is discovered is increasing. The researchers examined data from cancer registries in Los Angeles, Seattle and Detroit.Out of a pool of about 15,000 women under 45 with breast cancer, they found 438 who gave birth after diagnosis. They then matched each mother with up to 12 other patients of similar age, race and cancer status, among other factors, who had not given birth. They found that women who were diagnosed late in their pregnancy – those who gave birth within three months of the cancer being found – did fare poorly.The researchers speculated that this could be the result of an unknown effect that pregnancy has on the cancer’s spread, or of a delay in treatment for fear of harming the fetus. Women who were pregnant at the time of diagnosis but gave birth later than three months after diagnosis showed no difference in mortality rates. Women who conceived a child after diagnosis, in fact, appeared to cut their risk of death in half, compared with the women who did not have a child.But the researchers were not willing to conclude that pregnancy confers an actual survival advantage because of the possibility of what they called ‘healthy mother bias’ – that a woman’s assessment of her health and prospects would influence the decision on whether or not to get pregnant. (Source: New York Times, By JOHN O’NEIL, 12 August 2003)