Nursing Moms, the Let-Down Reflex and Milk Supply

Breastfeeding_mom

New moms may have the best intentions in wanting to breastfeed their newborns; but sometimes, nursing the baby doesn’t happen so effortlessly. This can lead both mom and infant to feel discouraged and want to give up trying.

But don’t give up! Your breast milk carries in it a large assortment of vital, life-sustaining nutrients, germ-fighting immunity cells, hormones, and many strains of beneficial bacteria that will colonize your baby’s gastrointestinal tract and aid digestion, as well as prevent allergies later on.

One of the more frustrating things that a nursing mom and baby may encounter is that the milk doesn’t seem to come out fast enough. Your baby may get tired of suckling and not getting much milk out. The infant’s unhappiness may in turn make mom feel unhappy and make her want to give up breastfeeding.

But the solution to this problem is to simply keep trying. With persistence and frequent nursing, your milk production will step up to meet your newborn’s individual needs — and your baby will likewise learn to relax and trust that the milk is in there and is coming.

The Milk Ejection Reflex

More often called the “let-down reflex,” it happens when the baby starts suckling, which stimulates the release of the hormone oxytocin into the mother’s system. Oxytocin causes myoepithelial cells, muscle-like cells surrounding the alveoli, to contract. Alveoli are hollow cavities lined with milk-secreting cells, or lactocytes. Alveoli band together to form many “lobules” in each breast; each lobule has a duct that drains into openings in the nipple. When the myoepithelial cells contract, the milk in the alveoli is squeezed into the ducts. This is how milk that’s already stored in the breast reaches the baby.

The more the infant sucks, the more oxytocin is released, and the more the alveoli will drain their milk contents. Conversely, when the baby doesn’t nurse very much (or at all), the breast sends the message to the brain to cut back production, and your milk will quickly start to decrease in volume.

For that reason, it is important to keep trying, until both you and your infant get “in sync” with one another; as the days go on, your breasts will learn how much milk needs to be produced to satisfy your baby’s needs. And likewise, your infant will learn to “go with the flow,” as it were, and just wait until the milk comes out.

Once your baby learns the rhythm of your milk’s flow, s/he will also realize that if s/he waits a little, another spurt will follow — milk ejection doesn’t just happen once during a feeding. Experts note that as many as 12 milk ejections or spurts have been recorded during one feeding (or pumping) session; the average number is 2.5 per feeding.

Each milk ejection initially releases an average of one ounce of milk, with the quantity decreasing as the feeding goes on. A few women eject more than an ounce at the start of each feeding.

Different Breast Lobules Produce Milk at Different Times

During a feeding, you may think that once the milk flow slows and the baby is becoming uninterested because of that, your breast is out of milk. But this is not the case. The breast’s many lobules are all producing milk, but at different stages — while one has released its contents, there are others that are about to. So, if you and your baby just wait a little while, more milk will flow out. As the weeks go on, your baby will learn to be patient and wait for the milk, until s/he is good and full.

As long as milk is removed, the breasts will continue to produce it. That’s why it’s important to keep draining the breasts when they become engorged.

If you are having problems breastfeeding and plan to consult with an expert, you need to continue to remove the milk often, even if it’s manually — you may store it in bottles and refrigerate it. (Note: Due to different hormonal contents between day and night milk, it is best to feed your baby milk expressed in the daytime, during the day; and milk that you express at night, during the night.) If you don’t drain the milk often, you will go from having abundant milk, to little or no milk in a matter of days or weeks. So, you’ll want to consult with your doctor or a lactation specialist sooner, rather than later.

As your baby grows and demands more milk, your breasts’ storage capacity will likely grow during the first few months. By the way, the size of your breasts does not necessarily determine how much milk they can hold; the number of well-developed milk glands inside the breasts is what counts: some smaller breasts may have a high density of these glands, and some larger breasts may have a low density.

Why It Is Important to Breastfeed Exclusively in the Beginning, for a Good Milk Supply

Nipple stimulation and removal of milk with frequent feedings send signals to the mother’s brain which in turn tailor how much milk the breasts produce. Breastfeeding your newborn often will help your body “calibrate,” as the process is called, the amount of milk that will be needed to nourish the infant in the months to come: your milk supply is determined by how often you breastfeed and remove milk in the first days and weeks after birth.

Though new moms may be tempted to supplement their breastfeeding with formula or give up nursing, due to a low milk supply, that is not advisable, as it will only decrease the mother’s milk production even more.

Exclusive breastfeeding, then, is recommended in the initial weeks — and better yet, in the first six months of life, as breast milk supplies your infant not only with all the nutrients he or she needs in those first six months, but it will promote good health in the years that follow.

By Cynthia Sanchez. A graduate of the University of Washington, Cynthia has extensive experience writing about health and wellness topics for different media.