Pumped milk and the milk a baby receives via nursing are not the same.
In order to best explain the difference between expressed milk and milk that a baby gets via nursing, I have to explain some of the mechanics of breast milk production and delivery.
A mother’s milk is constantly changing in composition to meet her child’s needs. A lot of people don’t realize that each time a baby nurses they get a different meal, and when a mom pumps, her baby is unable to signal to the breast what changes need to be made in the milk to suit his/her needs:
"A surprising fact is that the composition of breast milk changes with each feeding, so no matter what time of day it is, or what season, mother's milk will adjust to the specific needs of her baby. This is true for the nursing newborn or the nursing toddler- a mother's body will adjust to provide exactly what is needed nutritionally. So, as a child's vitamin and mineral requirements change, so will the concentration of these important nutrients in breast milk. One theory for this is that the baby's saliva signals specific nutritional requirements to the mother." (1)
While just one pumping session, or infrequent ones, aren’t likely to affect milk composition in the grand scheme of things, one can see how pumped breast milk vs. nursing at the breast can mean a slight deviation from the baby’s needs. Suppose a mother wants to go out and bring along some milk she pumped the other day. Maybe baby needed more of a certain vitamin and her body has that “in stock” now, but didn’t when she pumped. Maybe she’s been exposed to a new antibody or germ and her milk is producing some protection for her baby, and baby is missing out on it with what she pumped before. This may not be a problem if she is just going to nurse later, but that’s still one less meal custom made for baby.
Also, something a mom wouldn’t run into when nursing that can become an issue with pumped milk is excess lipase. “Lipase is an enzyme that is normally present in human milk and has several known beneficial functions: Lipases help keep milk fat well-mixed (emulsified) with the "whey" portion of the milk, and also keep the fat globules small so that they are easily digestible (Lawrence & Lawrence, p. 156).
Lipases also help to break down fats in the milk, so that fat soluble nutrients (vitamins A & D, for example) and free fatty acids (which help to protect baby from illness) are easily available to baby (Lawrence & Lawrence, p. 156).
The primary lipase in human milk, bile salt-stimulated lipase (BSSL), "has been found to be the major factor inactivating protozoans" (Lawrence & Lawrence, p. 203).”
When milk is pumped some mothers find that they have excess lipase. Excess lipase causes milk to smell sour or rancid, and if a mom didn’t scald the milk, it’s not fit to give the baby if it has soured.
“Scalding the milk will destroy some of the anti-infective properties of the milk and may lower some nutrient levels, but this is not likely to be an issue unless all of the milk that baby is receiving has been heat-treated.” (2)
A mom that has excess lipase that scalds her milk to give to baby also alters the composition and milk is less nutritious than if baby had simply nursed.
Pumping can cause health issues for mothers.
A baby (when nursing correctly) removes milk better than even a hospital grade pump. Say a mom pumps before she goes out and intends to feed the baby pumped milk to avoid nursing in public. When milk is not removed from the breast well enough, a mother runs the risk of getting plugged ducts, or even worse, mastitis. While pumping just once doesn’t guarantee a mother will get a plugged duct, it’s a risk she takes each time she pumps. (3)
Pumping can negatively impact a mother’s milk supply if the breasts are not emptied effectively. Milk production is supply and demand. The more milk removed, the more replaced. Since we know a baby removes milk best, pumping leaves behind milk and therefore signals to the breast that it doesn’t need to make more. Over time this can impact a mother’s milk supply. (4)
Another issue with pumping is that some moms just really don’t respond well to the pump
Pumping is hard work, time consuming, there are a lot of issues a mom could run into and really, it’s just not as enjoyable as nursing, which releases hormones that soothe both a mother and child. Milk storage is also time consuming and mothers have to be careful with milk so it doesn’t become contaminated. This can cause a great deal of stress on mom, which is unhealthy and ultimately unnecessary.
Please stop by NursingFreedom.org this Wednesday, December 22 for Part 2 of Pump and Go.
*Note: Please note this is NOT anti-exclusive pumping (EPing), EPing is very hard and takes a great deal of dedication from a mother, I applaud and commend any mother who has EPed for her child and want to state that breast milk in a bottle is far superior to formula. This conversation is solely for the purpose of stating what trouble pumping can entail, and if anything maybe give some insight as to what mothers who EP have had to face in their dedication to giving their child the best they can.
This article is edited from a previous version published at Life's a Salad Bar.
Anna is an army wife, mother to a "spirited" toddler, fitness coach, future lactation consultant and advocate of natural, gentle parenting. She stays busy and occasionally blogs (or rants) about her ideas and interests at Life's A Salad Bar.