Unhelpful Old Wives' Tales About Breastmilk Storage
You’d think that in this modern age—where we can test, measure, and analyze the tiniest cells and bits of bacteria—we’d provide mothers and babies with the breastfeeding facts they need for health and happiness. Unfortunately, as we worked to bring Ceres Chill’s breastmilk storage solutions to the world, we uncovered tedious and unsupported breastmilk storage “rules” that complicate an already challenging process for pumping moms.
Most recently, we have looked to science to tell us whether there is any support for the widespread belief that moms cannot add warm, freshly expressed milk to chilled milk.
Every time I encountered this rule, I thought, Why not? What happens if they add it? No one could ever answer this question for me, and there were never any research citations available. That really nagged at me as a pumping mom with a ton of work and barriers to breastfeeding already on my plate. I had friends throwing away ½ to 2 ounces of breastmilk at a time because they felt the amounts were too small to go through the process to pump, save, chill, and then combine.
Lisa M. Stellwagen, MD, FAAP Pediatrics (Primary Specialty) | Newborn Hospital Care
The Truth About Combining Warm and Chilled Breastmilk
I’m happy to report that real research by doctors in this field tells moms something great: not only can you add warm breastmilk to chilled milk, but doing so has health benefits for your baby!
Enter Lisa Stellwagen, MD, a newborn specialist and board-certified pediatrician. Dr. Stellwagen has been a pediatrician for 30 years, both in community and hospital settings, and is the medical director of the Newborn Service at UC San Diego Health. Her clinical expertise includes infant nutrition, breastmilk feeding, and newborn care. According to Dr. Stellwagen and her colleagues:
Hospitals have traditionally recommended that milk from each pump session should be individually stored, but this approach has not been validated.
Furthermore, their research—published in Breastfeeding Medicine (April 2013)—found that a single daily pooling strategy provides several important benefits over individualized collection:
✔ Consistent nutrient quality
✔ Equivalent bacterial content
✔ Improved maternal satisfaction
Making Breastfeeding & Pumping Easier
At Ceres Chill, we believe in science-based breastmilk storage solutions that make life easier for moms. That’s why we created the Ceres Chill OG Breastmilk Chiller—designed to keep expressed breastmilk safe for up to 20 hours without the need for a fridge or ice packs.
Want more guidance on breastmilk storage and pumping best practices? Check out our breastmilk storage guide for expert-backed breastfeeding tips.
Lisa M. Stellwagen, Yvonne E. Vaucher, Christina S. Chan, Taylor D. Montminy, and Jae H. Kim,
Breastfeeding Medicine Vol. 8, No. 2, published April 10, 2013