Can breastfeeding increase heart disease risk?
July 16, 2019
Can breastfeeding cause heart disease or make it worse? This question might seem mind-boggling at first glance. Women have been breastfeeding for millennia.
A 2019 survey out of Australia suggests that breastfeeding can actually decrease a woman’s risk of heart disease over time. But it considered only the traditional definition of “heart disease” – an umbrella term for a variety of conditions, including blood clots, heart attacks, and strokes.
There are two specific heart diseases – peripartum cardiomyopathy (PPCM) and Marfan syndrome – that have researchers wondering whether breastfeeding might actually make these patients’ conditions worse.
Potential heart-healthy effects of breastfeeding
In the aforementioned Australian survey, researchers asked more than 100,000 women ages 45 to 65 about their breastfeeding history, as well as certain heart disease risk factors such as socioeconomic status, body mass index, and alcohol use.
Researchers classified women into two groups: “ever breastfed” and “never breastfed.” The study excluded women who said they had been diagnosed with heart disease or were hospitalized for heart disease within the previous six years.
After controlling for heart-disease risk factors, researchers found that breastfeeding was associated with positive long-term health effects. Their results suggested women who breastfed had a 14% lower risk of hospitalization for heart disease complications and a 34% lower risk of death from heart disease than women who never breastfed.
These data aren’t conclusive because the survey was retrospective in nature, and the participants’ answers were self-reported. That said, the findings are encouraging for women with low-to-average heart disease risk who intend to breastfeed or have in the past.
However, when we consider PPCM and Marfan syndrome, the data are less clear.
"There are two specific heart diseases – peripartum cardiomyopathy (PPCM) and Marfan syndrome – that have researchers wondering whether breastfeeding might actually make these patients’ conditions worse."
Peripartum cardiomyopathy and breastfeeding
PPCM is a sudden dysfunction of a woman’s heart within six months of giving birth. PPCM affects about 1 in 1,000 women in the U.S., and symptoms are similar to heart failure in an older adult – the heart simply gives out, causing exhaustion and inability to perform daily activities.
While we’re not sure exactly what causes PPCM, research in mice suggests that prolactin, a hormone the body makes to induce and continue lactation, might play a role.
Because PPCM is uncommon, it’s tough to gather accurate data. But a small study of 100 women with PPCM found that the 15% who breastfed had better heart function and immunity, as well as similar cardiac recovery, compared to 85% of women who didn’t breastfeed. These results suggest that breastfeeding might be safe for women with PPCM, and only those who are severely ill should consider not breastfeeding to reduce heart complications.
As noted in this study, these outcomes contradict findings by the European Society of Cardiology Study Group but are similar to the outcomes of an internet-based survey in the U.S. However, given the size of the study and disparity of findings, more research is needed.
Related reading: Heart failure after pregnancy: Brittany’s story
Marfan syndrome and breastfeeding
Marfan syndrome is a genetic defect that causes the body to produce a protein that reduces the integrity of the heart’s arterial walls. Patients with Marfan syndrome are at greater risk of aortic dissection – a tear in the lining of the aorta, which is the main artery that supplies oxygen to the rest of the body.
Researchers are investigating whether another hormone, oxytocin, affects women’s heart health while breastfeeding. The body produces oxytocin to induce labor and, according to recent studies, might increase the risk of aortic dissection.
The body continues to produce oxytocin during lactation, and researchers are currently conducting a study to find out whether breastfeeding can exacerbate Marfan syndrome.
Related reading: Complications during pregnancy can predict future heart disease risk
Breast pumping as an alternative
Dr. Shivani Patel explains the advantages of exclusive pumping, and why some women prefer it over breastfeeding.
To breastfeed, or not to breastfeed?
While conclusions about breastfeeding and heart disease risk vary, the consensus among doctors at UT Southwestern is that patients should choose to breastfeed (or not) after thorough conversations with their Ob/Gyn, cardiologist, and maternal-fetal medicine specialist.
In these conversations, we discuss with patients their nutrition and exercise routines, personal drive to breastfeed, total number of pregnancies, degree of heart dysfunction, and level of physical endurance based on their heart disease symptoms. Some women might not be physically able to breastfeed, while some women and their doctors might feel confident that the benefits of breastfeeding outweigh the risks. For women who cannot breastfeed, donor breast milk is a great option.
We guide patients through their options on a case-by-case basis. To date, we’ve never recommended a patient stop breastfeeding because of PPCM or Marfan syndrome. This is in line with an opinion published in the Journal of the American College of Cardiology, which suggests doctors carefully weigh the risks and benefits before recommending that women with heart disease stop nursing.
Ultimately, our goal is healthy moms and babies. Whether you choose to breastfeed or bottle feed, we will provide education and resources to support your health and the health of your baby.
PTSD after pregnancy
You may associate post-traumatic stress disorder with survivors of assault, war, or natural disasters. But as maternal-fetal specialist Dr. Shivani Patel will tell you, symptoms of PTSD can weigh heavy on moms who had complex pregnancies. She knows from personal experience.