Breast Milk Production and How Breastfeeding Works

Have you ever stopped to think about how breast milk is made or the body's process that provides those sweet breastfeeding moments with your little one? Let’s talk about your body and how breastfeeding works!

How Does Breastfeeding Work?

The hormone progesterone plays a key role in breastfeeding, both when you’re pregnant and after you give birth. While you’re still pregnant, there's more progesterone in your body than usual, which helps stop your breasts from expressing the milk that you're starting to produce. If you happened to notice some leakage during pregnancy, don’t worry, that’s totally normal!

What is Colostrum?

Towards the end of your pregnancy, your breasts will feel “full". That’s the colostrum (nutrient-packed “first milk”) beginning to be produced! Once you give birth, a couple of things happen to allow your milk to flow: the hormone prolactin increases, and progesterone levels drop. The first few breastfeeding meals after birth are small for baby, but full of that liquid gold – colostrum – and all the vital nutrients your newborn needs.

Colostrum also provides protection for your baby against infections. Plus, it's higher in protein and lower in sugar and fat than mature breast milk. Your body will continue to produce colostrum for several days after your little one's debut before transitioning into a more mature breast milk. This transition is often referred to as your "milk coming in". 

What is Breastfeeding Letdown?

Breast milk is produced in the glandular tissue (alveoli) of the breasts. The smooth muscle tissue around each tiny milk-producing cell contracts when hormones are released. Letdown occurs when these contractions propel milk down the milk ducts to the openings in the nipple and is triggered by your baby’s cry and touch, nipple stimulation, and suckling.

During a feeding, you’ll have several letdowns, but during the first letdown you may notice a tingling or throbbing sensation in your breasts. This is totally normal and is caused by the milk ducts dilating as your milk flows. Since milk production operates on a supply and demand basis, frequent breastfeeding will stimulate milk production and keep your supply up.

Why Does Breast Milk Change as Baby Grows?

As your little one grows, your breast milk changes to keep up with your baby’s evolving nutritional needs. Your breast milk will even adapt if you or your baby are exposed to germs or a virus by increasing its anti-infective properties. Your output also increases in volume as you continue to nurse and pump.

As your baby grows and begins eating solids, they'll naturally nurse less frequently. At that time, your breast milk changes again by developing more antibodies and higher fat content to ensure he or she gets the highest nutritional value possible from the decreased number of feedings. At this point in your breastfeeding journey, your breast milk production will likely decline.

Breast milk production is a beautiful, amazing, and fascinating process that makes breastfeeding your baby possible. As a breastfeeding parent, you should be proud of the incredible nutrition you are providing for your little one!