New moms are well aware of the dozens of ways babies benefit from breast-milk, but they often don’t realize that nursing a child also benefits their own bodies. Studies have found that women who breast-fed have a reduced risk of osteoporosis and ovarian cancer, as well as high blood pressure and heart disease decades later. Also they return to their pre-pregnancy weight faster and experience less postpartum bleeding.
And now a new study indicates that women who breast-feed their babies even for short periods of time may lower their risk of developing premenopausal breast cancer if they have a family history of the disease.
The New York Times reports:
Although several studies have found that lactation is protective against breast cancer, the new report found little effect for premenopausal women over all. But for women with an immediate relative, like a mother or a sister, who had breast cancer, those who breast-fed had a 59 percent lower risk of premenopausal breast cancer. That is closer in line with the risk for women who had no disease in the family, the study found.
“I was sort of stunned,” said Dr. Alison M. Stuebe, the first author of the study and an assistant professor of obstetrics and gynecology at the University of North Carolina, Chapel Hill. “It’s an impressive reduction in risk. Other studies either hadn’t looked at this or didn’t include enough women with a family history to find a statistically significant difference.”
The study appears in the most recent issue of The Archives of Internal Medicine. Researchers used information from 60,075 women who participated in the second Harvard Nurses’ Health Study between 1997 and 2005. All of the women had given birth at least once and 87 percent of them breast-fed. The observational trial first interviewed women in 1997 and followed them until 2005. By June 2005 doctors had diagnosed premenopausal breast cancer in 608 women.
The women whose mother or sister had breast cancer but who had breast-fed for as little as a month had a 59 percent lower risk of breast cancer compared to those who had an affected relative but refrained from breast-feeding. Women without a family history of breast cancer did not show the same link between breast cancer and nursing.
More research is necessary to show that the reduced risk is the result of breast-feeding, rather than some other factor common to women who nurse. “But Dr. Stuebe suggested that breast-feeding may prove just as effective a strategy for high-risk women as the use of Tamoxifen, a drug that interferes with estrogen activity and is often used in high-risk women to reduce breast cancer risk,” The Times reported.
Another interesting discovery was made from this study: Women who took drugs to prevent the formation of milk were at lower risk for breast cancer than those who refrained from breast-feeding but did not use lactation-suppressing drugs. This suggests “it’s more of the effect of milk being taken out of the breast tissue after pregnancy that’s beneficial,” Dr. Stuebe told Health Day News. “We know that just being pregnant reduces the risk of breast cancer compared with not having been pregnant. Getting milk out afterward appears to be part of the phenomenon.”