💡 L’essentiel à retenir : Breast milk is a living substance, whose composition naturally varies according to the time of day, the duration of the feed and the baby’s saliva. Although beneficial, it can lead to slight changes in this composition: lower fat content, loss of nutrients, or alteration of the microbiome. These adjustments are limited, however, and do not call into question the high quality of the milk drawn.
⏱️ Reading Time : 3min30
Breast pumps have established themselves as a valuable solution for mothers who need to reconcile breastfeeding and going back to work. But this practice raises a legitimate question: does pumping alter the composition of breast milk? Thanks to recent research, we now know that the composition of breast milk is naturally variable… and that the method of expression, as well as storage, can also influence some of its qualities.
A living, evolving milk
Unlike industrial infant milk, breast milk is a living liquid whose composition is constantly evolving:
- during a single feed,
- depending on the time of day,
- depending on the infant’s age,
- and even in response to the child’s saliva.
For example, hindmilk (milk expressed at the end of a feed) is much richer in lipids than foremilk, which is more watery and rich in lactose. This natural progression helps to satiate the baby while meeting his nutritional needs.
Breastpump and composition: some possible differences
When a mother expresses milk, certain parameters change:
1. Less fat if extraction is incomplete
One of the most notable adjustments concerns fat content. As the aftermilk is thicker, it can be more difficult to extract, particularly with a poorly adapted electric breast pump or if the session is too short. As a result, the milk extracted may contain slightly less fat.
👉 Tip: prolonging sessions slightly and mixing the expressed milk well before feeding helps to compensate for this imbalance.
2. A variation depending on the time of day
Studies show that morning milk naturally contains less fat than afternoon or evening milk. It also contains more melatonin at night, a hormone that promotes baby’s sleep.
👉 Tip: for moms who pump at different times of the day, it can be useful to label the time of pumping, especially if you want to preserve the specific benefits of night milk.
3. The role of equipment and hygiene
Pumping involves handling the milk in a way that direct breastfeeding does not. Contact with plastic parts or poorly cleaned containers can slightly alter the microbiome of breast milk. Some studies have observed more bacteria in milk expressed with poorly sterilized personal equipment than in milk expressed under sterile hospital conditions.
👉 Tip: proper cleaning of the breast pump, bottles and nipple shields is essential to preserve milk quality.
4. The consequences of storage
The preservation of breast milk can influence its nutritional richness. Studies have shown :
- a progressive reduction in vitamin C after extraction,
- a drop in the activity of immune proteins such as IgA or lysozyme after freezing,
- a loss of fat after several days at -20°C.
👉 Tip: use short, appropriate storage periods (refrigerate within 4 days) and avoid microwaving to preserve the milk’s properties.
When the breast does more than feed
The direct contact between baby’s mouth and breast creates a unique interaction. The baby’s saliva can transmit signals to the mother’s body, influencing the composition of the milk in real time. This synergy is impossible to reproduce with a breast pump, but it does not diminish the value of the milk pumped: it remains highly beneficial for the baby.
So, is the breast pump really “less good”?
Absolutely not. Although some changes in composition may occur, the milk pumped remains of good nutritional quality.
The important thing to remember is that :
- yes, the breast pump has a slight influence on the composition of the milk,
- no, this does not call into question its major benefits.
At Pachamama Solutions, we support young mothers who wish to return to an active professional life while continuing to breastfeed. With this in mind, our breast pumping chairs are designed to provide a calm, ergonomic and intimate space, promoting quality milk extraction.
Conclusion
Breast pumping is much more than just a technical gesture: it’s an act of the heart. While pumping may lead to variations in milk composition, the benefits of breast milk are immense.
Differences in lipids, microbiome or vitamins are generally moderate, and often offset by good pumping, storage and hygiene practices. The most important thing is that your baby always benefits from the best that breast milk has to offer: tailor-made nutrition, powerful immune protection, and a precious bond with his mother.
At Pachamama Solutions, we deeply believe that a caring, well-equipped work environment enables young mothers to continue breastfeeding with peace of mind. By offering them comfortable and adapted spaces, we support their choice.
Autrice
Camille Desclée
Experte en QVT &
Co-fondatrice de Pachamama Solutions
Camille Desclée est experte en Qualité de Vie au Travail (QVT) et co-fondatrice de Pachamama Solutions, une entreprise qui œuvre pour une meilleure prise en compte de la parentalité en milieu professionnel. Elle développe notamment des solutions concrètes comme des fauteuils de tire-allaitement pour les espaces de travail, afin de favoriser le bien-être des jeunes mères et l’égalité en entreprise.