An analysis of 17 past studies suggests that while breast-feeding for any period of time appears to lower a woman’s risk of endometrial cancer, mothers who breast-fed for the recommended six months lowered their risk even further.
Surpassing the 6-9 month recommended timeframe for breast-feeding seemed to have little benefit, the researchers said, but those who had ever breast-fed their children were 11 percent less likely than women who had children but didn’t breast-feed to be diagnosed with endometrial cancer, Reuters reported.
“Cancer of the uterus is becoming more common and we need to try to prevent it,” lead author Susan Jordan, of the QIMR Berghofer Medical Research Institute in Brisbane, Australia, told Reuters. “The more women know about the things they can do to reduce their risks of future cancer diagnosis, the better.”
For the report, which was published in Obstetrics and Gynecology, researchers used data compiled in the Epidemiology of Endometrial Cancer Consortium, including 10 from the United States and others from Canada, China, Europe and Austrialia, Reuters reported. They looked at more than 26,000 women who had ever had a child, whether they breast-fed, and for how long. Among the women, researchers discovered about 9,000 had been diagnosed with endometrial cancer.
Even after accounting for other risk factors such as age, race, education, oral contraceptive use, menopausal status, years since last pregnancy and body mass index, the suggested protective benefit of breast-feeding remained, Reuters reported.
The authorites noted that the study doesn’t prove that breast-feeding helps protect against endometrial cancer, but it’s plausible because estrogen, which stimulates the growth of the cancer, is suppressed during breast-feeding.
“Although this piece of evidence by itself may not convince women to breast-feed, it contributes to the overall picture of health gains that can come from breast-feeding,” Jordan told Reuters.
Reuters contributed to this report.