Breastfeeding A to Z

Understanding How Breastmilk Is Made

Remember, mother’s do not start the day with a quart (liter) of milk on each side and slowly use it over the course of the day.  You always have some milk present in the breast but milk is made whenever the nipple is stimulated. (1)  This is a very efficient system.  Milk is made when it is needed and there is a small storage area for immediate use.  This happens whether your baby is breastfeeding or if you are using a breast pump.  If you are concerned about having enough milk, feed your baby more frequently or for longer periods of time (if baby is agreeable) or use a breast pump in addition to breastfeeding.  The more the nipple is stimulated, the more milk is made.

In the first few days after delivery, it may be difficult to tell if the baby is swallowing.  The volume of milk is very small.  Colostrum, the first milk that your baby will receive, is made in teaspoons (milliliters) and is packed with nutrition.  This is because your baby’s stomach is a tiny place.

Your baby’s stomach holds approximately 7 milliliters (ml) (about 1 teaspoon) on the first day of life.  When they are three days old your baby’s stomach can hold about 3/4-1 ounce (approx. 27 ml) at a time.  By the end of their first week of life your baby’s stomach will hold about 1.5-2 ounces (approx. 57 ml). (1) That is roughly the size of your baby’s closed fist or a golf ball.

Also, in your baby’s first day of life their stomach does not stretch to accommodate more liquid. (1)

Babies are frequently overfed from our misunderstanding of how much is normal for a newborn to consume–or that more is better.  Baby’s stomach will expand over the first month of life, but this small volume of colostrum in the first few days of life, is just the right amount while your baby is learning to coordinate their sucking, swallowing and breathing, before they have larger volume of milk to deal with too.  (1)

Colostrum also serves to coat your baby’s intestinal tract to protect your baby from illness and acts as a laxative to help baby start stooling (having dirty diapers).  (1) Two to four days after delivery, your milk volume will increase.  This is sometimes referred to as your milk “coming in”.  Realize you always have milk–it’s just the volume changes.  When the volume starts to pick up, you may hear “glug, glug” or gulping when your baby starts to eat and the milk is coming more forcefully.  Once the baby gets into a rhythm it may sound more like a “ca ca” sound.

  1. Mannel, R, Marten, PJ, Walker, M, Core Curriculum for Lactation Consultant Practice, 3rd edition, Burlington MA, Jones & Bartlett Learning, 3013, pp 291, 306-7, 357, 594.