CentraCare Study Finds Antenatal Milk Expression May Help Mothers Breastfeed Longer

What if preparing for breastfeeding could begin before your baby is born?

That's the question behind the AMETHYST BLUE Study, a CentraCare research project exploring whether antenatal milk expression (AME), also called prenatal hand expression or colostrum harvesting, can improve breastfeeding outcomes for new mothers.

The idea for the study grew during the COVID-19 pandemic, when formula shortages prompted greater interest in collecting colostrum before birth. But for Edward Martin-Chaffee, MD, a pediatric cardiologist and neonatologist at CentraCare, and Jeanne Friebe, a CentraCare lactation specialist, the potential benefits extended far beyond replacing formula.

"We know that longer breastfeeding is beneficial for babies and mothers," Dr. Martin-Chaffee explained during an interview about the study. He was especially interested in whether AME could help mothers breastfeed exclusively for longer and reduce the need for formula supplementation after delivery.

What is antenatal milk expression?

AME is the practice of hand expressing small amounts of colostrum, the first milk your body produces, during the final weeks of pregnancy after receiving approval from your healthcare provider.

The collected colostrum is frozen and brought to the hospital, where it can be used if supplementation is needed after birth. Jeanne says interest in the practice has grown rapidly as more families learn about its benefits and become interested in using colostrum when appropriate.

What the researchers found

The AMETHYST BLUE Study followed 121 first-time mothers who were at least 37 weeks pregnant. Ninety-two participants chose to practice AME before delivery, while 29 did not. Researchers compared breastfeeding outcomes during the first six months after birth. The results were encouraging.

Mothers who practiced AME experienced their milk coming in about one day earlier than mothers who did not. Researchers also found that nearly 45% of mothers who practiced AME were exclusively breastfeeding at six months, compared with about 29% of those who did not participate.

Just as importantly, researchers found no evidence that practicing AME caused mothers to go into labor earlier. Both groups delivered at approximately the same point in pregnancy.

While the study found an association, not proof that AME directly caused these outcomes, Dr. Martin-Chaffee believes the findings are meaningful and warrant continued research.

More than milk — building confidence

For Jeanne, one of the biggest benefits of antenatal milk expression is confidence.

She believes learning hand-expression techniques before birth helps mothers become more familiar with breastfeeding and their own breast anatomy. It also gives a mother a way to express milk if a breast pump isn't immediately effective or available.

AME is best accomplished through hand expression and is encouraged to help achieve optimal results rather than relying on a breast pump. The milk volume collected through a breast pump is generally small and gets trapped and lost in the pump parts. Hand expression gets every little drop.

She also emphasizes that every mother's experience is different.

"If there is a mother that tries and it is not successful, it may be the technique," she shared. "That does not mean you won't make milk." Lactation specialists are available to help families learn the technique and answer questions along the way.

A commitment to breastfeeding support

The AMETHYST BLUE Study is just one example of CentraCare's commitment to research and breastfeeding families.

Jeanne highlighted the many resources available, including prenatal lactation support, bedside lactation consultants, breastfeeding classes, the free Bump to Baby 360 app, Baby Café support groups and ongoing education for physicians and care teams. These services help families receive support before, during and after birth.

If you're pregnant and interested in learning whether antenatal milk expression is right for you, talk with your prenatal care provider or a lactation specialist. They can help determine whether AME is appropriate for your pregnancy and teach you how to safely get started.