Study to Examine Why Some Breastfeeding Moms Struggle with Milk Supply

K. Arcaro & S. Schneider

UMass Amherst researchers led by Kathleen Arcaro, professor of veterinary and animal sciences, have been awarded a $3.3 million NIH grant to analyze impacts of mammary gland permeability.

Human milk is known to provide numerous health benefits to infants, including lower risks of infection, childhood obesity, allergies and autoimmune diseases, which is why the American Academy of Pediatrics and the World Health Organization recommend exclusive breastfeeding for the first six months of life.

Yet some 60% of new parents struggle to meet their breast-feeding goals, and an inadequate milk supply is the most frequent reason given for earlier-than-desired weaning.

A team of breast cancer-breast milk researchers from the University of Massachusetts Amherst, UMass Chan Medical School-Baystate and the University of New Mexico Health will tackle this conundrum by examining mammary gland permeability in breastfeeding parents. They have received a five-year, $3.3 million grant from the National Institute of Child Health and Development for the study, which will recruit 400 pregnant women planning to breastfeed – 200 from the Springfield, Mass., area and 200 from the Albuquerque, N.M., area.

“The purpose of this research is to learn about factors that contribute to a new parent’s milk supply and how the milk supply affects the baby,” says co-lead investigator Kathleen Arcaro, professor of veterinary and animal sciences (VASCI) at UMass Amherst.

“This is going to be a really interesting study,” adds co-lead investigator Sallie Schneider, director of HistoSpring, the biospecimen resource and histological analysis facility at Pioneer Valley Life Sciences Institute, a partnership between UMass Amherst and Baystate Medical Center, and associate professor at UMass Chan Medical School-Baystate. “Why do women who want to breastfeed feel they can’t, especially if it’s due to their perception that they’re not producing enough milk?”

It is well known in the dairy industry that increased mammary gland permeability reduces both the quantity and quality of the milk that cows produce. Dairy cows are routinely tested for signs of increased permeability by measuring the sodium and potassium in their milk, among other tests.  

“Surprisingly, there is no routine test for women, and the parameters indicating normal functioning in established lactation of the human mammary gland are largely unknown,” Arcaro notes.

“From our preliminary studies we found that a number of women have markers  suggesting that their increased permeability may be due to an overgrowth of pathogenic bacteria or an inflammatory reaction,” Schneider says. “While they don’t have any symptoms of something like full-blown mastitis or fever, the profile suggests reduced production of milk.”

The research team, including lactation specialist and nurse Katie Kivlighan, assistant professor at the University of New Mexico Health, will start recruiting participants for their comprehensive, longitudinal study later in the fall. They will collect information on the women’s health and lactation desires before they give birth. Then for five months, they will collect and examine samples of breast milk and infant fecal material to determine the extent to which elevated permeability of the mammary gland is associated with nutrient content, immune profile and the milk microbiome, as well as effects on infant health, including the infant’s gut microbiome.

They will continue the study with questionnaires at eight months and one year, looking to uncover factors associated with increased mammary gland permeability. The goal is to understand disparities in breastfeeding success rates and to identify potential interventions.

The study will focus on recruiting an abundance of Black, Latina and Native American women because the team’s preliminary research indicated that women of color experience higher rates of elevated mammary permeability and increased inflammatory profiles in milk. 

“Stress itself could be causing it,” Arcaro says, “as there is ample evidence indicating that being Black in our culture or being poor is stressful.” 

The study is dubbed Breastfeeding CHAMPS (Child Health and Mammary Permeability Study). “Our long-term goal,” Arcaro says, “is to provide parents with knowledge about their milk to help them reach their personal lactation goals.”