November 07, 2018
Few women report being told by their obstetrician that prolonged breastfeeding, from 6 to 12 months, can reduce their risk of getting breast cancer, according to a study published online October 25 in Breastfeeding Medicine.
"The protective effects of breastfeeding against developing breast cancer are well known, but despite this, less than 20% of the women in our survey reported that they actually received this information from their healthcare provider. This needs to change," the study's senior author, Bhuvaneswari Ramaswamy, MD, from the Ohio State University Comprehensive Cancer Center, Columbus, told Medscape Medical News.
This information, although important for all women, is especially so for African American women, who, when diagnosed with breast cancer, have a 30% to 40% greater chance of dying from the disease than white women.
"One of my research interests is cancer disparities, and many population and epidemiological studies show that African American women have a higher risk of developing more aggressive triple-negative breast cancers," Ramaswamy commented. "Yet, they have higher parity and a lower prevalence of breastfeeding.
"Newer data show that breastfeeding appears to lower the risk of developing triple-negative breast cancer, and if we are looking at cancer disparities, this might be one of the things that explain why African American women have higher mortality from breast cancer," Ramaswamy said.
"We also know that women native to Africa have higher rates of breastfeeding and lower rates of breast cancer," she added.
Survey of New Mothers
Ramaswamy surveyed new mothers to find out how many had been informed that prolonged breastfeeding was beneficial to their health after her own informal poll of her friends and colleagues revealed that none had received such information from their healthcare providers.
"Not one time did any of my healthcare providers tell me that breastfeeding is important for my own health. Everybody knows it is good for the baby, but nobody said breastfeeding for 6 months or 12 months can reduce the risk of breast cancer. Then I talked to all my friends and colleagues and asked them how many were actually told that, and literally none of them had been," Ramaswamy said.
Her team surveyed 724 women aged 18 to 50 who had had at least one live birth. Participants were recruited through primary care practices and a national clinical research registry.
Although most of the women (92%; n = 667) had chosen to breastfeed, only 56% (n = 407) reported that they were aware of the link between prolonged breastfeeding and breast cancer risk reduction before they made the decision to do so, and a little more than a third of these women (36.4%) said this knowledge affected their decision to breastfeed.
Of the 39 women who did not breastfeed, 23 (59.0%) reported that awareness of such a risk reduction would have influenced their decision to breastfeed.
However, only 120 of the 724 respondents (16.6%) indicated that they had received this information from healthcare providers.
Women who had received this knowledge breastfed longer than those without this knowledge (13.2 months vs 9.3 months; P < .001).
More white women (76.4%) breastfed for longer than 6 months than African American women (63.2%; P = .011).
A Difficult Decision
"I understand that breastfeeding is a difficult decision to make. It's a huge commitment, and there are many factors that may prevent a woman from being able to breastfeed, but at least women should be armed with full information about breastfeeding," Ramaswamy said.
"Only 16% of the women in our survey who had this knowledge got it from their healthcare provider. Almost everybody else got it through the Internet. But if the healthcare provider conveys this information, we know from other studies that there is a higher take-up rate," she said.
"It should not be left up to the women to find this information for herself," she argued. Clinicians see a mother for several months, and "informing her should be part of her healthcare," Ramaswamy said.
How breastfeeding affects breast cancer risk is unclear, but research suggests it may be related to proinflammatory processes coordinated through activation of STAT3 (signal transducer and activator of transcription 3).
"This is one of the areas of research we are pursuing in my lab. We are trying to discover the biological mechanisms underlying the connection between breastfeeding and breast cancer risk, particularly difficult-to-treat triple-negative breast cancers. Hopefully this will help us identify prevention strategies for mothers who are unable to breastfeed," Ramaswamy said.
"I certainly don't want to come across as saying every mother should breastfeed. That is not feasible. The last thing I want to do is propose that women go back home and leave the workforce. But we do need a multipronged approach, and the first is to improve awareness of the benefits to the mother, so that we can all be on the same playing field," she said.
About one third of women (34%) in the United States now breastfeed for at least 1 year, compared with 22% in 2007, Susan Crowe, MD, from Stanford University, in California, said recently. The number of those who have ever breastfed or have breastfed for up to 6 months has increased by similarly substantial margins, and rates of exclusive breastfeeding to 3 months and 6 months are also increasing, she said. Crowe presented these data in April 2018 at the annual meeting of the American College of Obstetricians and Gynecologists, as reported at the time by Medscape Medical News.
The study was funded by the Stefanie Spielman Breast Center. Dr Ramaswamy has disclosed no relevant financial relationships.