How Breastfeeding Works
Breastfeeding is a natural way to feed a baby. Babies are born with reflexes that help them find the breast and begin nursing. But for mother and baby both, breastfeeding is a learned art. In the past, little girls grew up watching experienced mothers putting babies to breast. Today, many women have never seen anyone breastfeed before being handed their own first baby. Without assistance, learning how to position and latch the baby can seem difficult. Mothers also need help interpreting feeding cues and in being able to tell whether their baby is feeding well. It doesn’t quite seem fair that mothers must learn these new skills during a time when they are tired and still recovering from childbirth! The first few weeks can be challenging, but with support, mothers can enjoy the special intimacy and vital health benefits provided by breastfeeding.
How Your Breasts Produce Milk
During pregnancy hormonal changes cause branching structures inside your breasts to grow. These structures resemble a tree heavy with small, ripe berries. The bunches of ‘fruit’ are called alveoli. They are tiny clusters of milk-making cells that drain into the branching canals called ducts.
For the first few days after your baby is born, the breasts produce colostrum. Colostrum is thick -- rather like condensed milk -- and probably helps prevent choking as the baby learns to feed. Colostrum is produced in small amounts, providing just a few swallows at each of the early feeds. This is perfect for the baby, who must master breathing first, and whose tiny stomach isn’t ready for large feedings yet. Rich in powerful immune factors that prime the baby’s immature system, colostrum protects against infection. It also provides a laxative effect, helping the baby quickly pass the meconium, the black, sticky, first bowel movements. Quick passage of meconium helps protect the baby from developing jaundice.
Sometime between Day 2 and Day 6 postpartum, your milk will come in. This sudden onset of copious milk production is a normal event called engorgement. Once milk production adjusts to the needs of your baby, mature lactation begins. By this time, early concerns with sore nipples, latch-on, and other problems have been resolved. From then on, milk supply is controlled by how frequently the breasts are thoroughly drained.
In between feedings, the clusters of alveoli and the milk ducts fill up with milk. This makes the breasts feel heavy when it is time for the baby to nurse. As the baby sucks, stimulation of the nipple causes the mother’s pituitary gland, located in the brain, to release oxytocin. Oxytocin causes contractions in the muscle cells that surround the alveoli. These contractions squeeze milk out of the alveoli and cause the ducts to expand, pushing milk toward the nipple. In a beautiful system of give and take, the breast propels milk as the baby sucks.
Some mothers can feel this hormonally induced release. They describe it as a tingling or rushing sensation. Surprising at first, most women come to experience it as a pleasant, and soothing sensation. This is referred to as the “let-down,” or milk ejection reflex (MER). There are mothers who do not experience the sensation directly, but observe that the other breast will begin to leak or the baby will start to gulp. Other signs that a milk ejection reflex (MER) is occurring are a sense of thirst, or a sudden feeling of relaxation or even sleepiness.
The milk ejection reflex (MER) can be affected by stress, anxiety, or pain. This is why is it so important for breastfeeding mothers to have the support and care of their families as they recover from childbirth.
The key message to remember is that help is available. Please reach out to someone if breastfeeding is painful or difficult or if you are concerned that your baby is not feeding well.
Content provided with permission from Medela, Inc.
For more information or to discuss lactation support concerns please contact Partners Employee Assistance Program at 1-866-724-4EAP.
In case of emergency, please call 911 or your local hospital emergency service.
This content was last modified on: 08/21/2008