Benefits of breast milk
Time to read: 2 min.

Dr. Danielle Prime, a distinguished member of the Medela Medical Research Team, is here to share her insights into the latest advancements in human milk and lactation research. We'll explore practical advice for clinicians, including how to optimize milk removal by understanding infant sucking behavior and using proper pump settings, particularly for mothers navigating supply challenges or seeking to maximize their pumping routine.
Infants utilise two key styles of sucking rhythms: non-nutritive and nutritive. During a single feeding, babies instinctively switch between the two styles of sucking cycles. The non-nutritive cycle is crucial for breast stimulation and triggering milk ejection. These are rapid (over 100-120 sucking cycles per minute), shorter sucks with a weaker vacuum, often accompanied by little to no milk flow. This initial rapid sucking is vital in the first days after birth, when only colostrum is present, to stimulate the breast and program future milk supply. Babies continue using this rhythm to trigger milk to flow even after milk ‘comes in’. The nutritive sucking cycle, on the other hand, is for milk removal and it becomes predominant when milk is available and babies can coordinate sucking, swallowing, and breathing. These sucks are longer, slower (around 60 sucking cycles per minute), and generate a stronger, sustained vacuum, leading to significant milk removal.
We've translated these infant suckling patterns into pump technology. Medela's Initiation Technology™ mimics the infant's specific sucking patterns during the first days post-birth, which are characterized by numerous non-nutritive cycles, pauses, and brief periods of nutritive cycles to express colostrum. Research, such as Professor Paula Meier's study, shows that mothers exposed to this baby-like rhythm early on demonstrated better long-term milk production outcome. For established lactation, the typical rhythms are incorporated into two-phase technology, which all pumps utilize. This means pumps have distinct modes to trigger milk ejection and then to extract milk efficiently.
Babies instinctively regulate the vacuum level at the breast. They intuitively know how much vacuum to build, how long to hold it, and when to release it. Research shows a direct correlation: the peak vacuum a baby reaches is associated with greater milk output. Medela breast pumps are designed to mimic this natural rhythm closely. For the best outcome, when milk flows, mothers are encouraged to be in the expression phase of the pump and to maximize the vacuum level such that the pump is effective while maintaining comfort. This level is called Maximum Comfort Vacuum (MCV). This isn't necessarily the highest vacuum level on the pump; instead, it's the highest vacuum level a mother can tolerate without feeling discomfort.
Comfort is paramount, as it directly impacts milk output. If a mother is uncomfortable, it can inhibit her milk ejection reflex, resulting in reduced milk output. A common mistake is mothers pumping at uncomfortable, high vacuum levels, believing ‘stronger is better’. This often leads to pain and less milk. Guiding them to their MCV, even if it's lower than anticipated, significantly improves comfort and milk output. Remind them that the most powerful pump isn't always the best; the goal is to balance comfort and efficiency.
The MCV level is highly individual – what's comfortable for one mother might be too low or too high for another. It's also important to note that a mother's preferred MCV can change over time, often increasing and stabilizing as breastfeeding becomes more established. That is why I advise mothers to experiment with pumping settings and adjust the vacuum throughout a pumping session, as well as over the entire breastfeeding journey. Finding this personalized sweet spot of comfort and efficiency is crucial for successful pumping outcomes.
Not necessarily. Higher peak vacuum is primarily essential when milk is flowing (during nutritive sucking). In the initial non-nutritive cycles or ‘stimulation phase’ of the pump, there is no association between peak vacuum and triggering milk ejection faster, so striving for extreme ‘strength’ is not beneficial then.
Each mother has a unique milk flow profile, the individual pattern of milk ejections and pauses throughout a session. It means each mother differs in how a feeding (or pumping) session looks: how long it takes to remove the available milk, after how many minutes of stimulation milk starts to flow, whether milk flows continuously or with breaks, and even what mothers feel in their breasts. Understanding a mother's flow profile allows for true personalization. For instance, we can advise her when to stop pumping if her flow stops after the last milk ejection has occurred. This profile also helps explain why some mothers might need to pump longer than others. Mothers can experience significant psychological benefits when they understand their milk flow profile, as this knowledge removes the urge to compare their breastfeeding or pumping routine to that of other moms. This reinforcement of their individuality can profoundly enhance the overall success of their breastfeeding journey. This profile is consistent whether the mother is breastfeeding or pumping, across sessions, in subsequent lactations, and even between left and right breasts. By identifying this unique pattern, clinicians can provide tailored advice, optimizing each mother's breastfeeding and pumping journey.
Focus on optimizing the first let-down, as one third of the milk is removed during this period of the session. After the initial stimulation, once milk starts to flow, mothers should immediately switch to extraction mode and increase the vacuum to their Maximum Comfort Vacuum for efficiency. Generally, when milk is flowing, a slow mode with a higher vacuum is needed. It's okay to lower the vacuum temporarily between let-downs for comfort. While the mother’s milk flow profile determines session length, pumping frequency is more crucial than duration. Pumping every few hours is generally more efficient than long intervals between sessions. Finally, remember that avoiding stress and distractions while pumping can significantly improve your milk outcome.
The key takeaway is the power of personalization and individualization in breastfeeding support. Our ongoing research into infant sucking, vacuum, and milk flow profiles continually informs Medela technology, enabling us to mimic natural infant sucking as closely as possible. This growing understanding empowers healthcare providers to offer increasingly tailored and effective support, ultimately fostering positive breastfeeding journeys for mothers.
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