Breast milk is fascinating stuff! It changes dramatically during the course of a feeding. The first milk to spurt out (foremilk) is loaded with protein and antibodies, and it has extra water to satisfy your baby’s thirst. But after 10 to 15 minutes, as the breast empties, the milk flow slows and gets richer, releasing the sweet, creamy hindmilk.
Some experts worry that feeding a baby for 5 to 10 minutes on each breast will fill the baby with the more watery foremilk and lead to more night waking. They think that the baby must get the rich hindmilk to make him sleepy (like a heavy meal makes us drowsy).
Others believe that babies drink down more milk when they’re given both sides during each meal. (More milk flows quickly during the first minutes of a feeding; then it slows down to a slow drip, drip, drip.)
Here is my personal recommendation: Try both ways to see what’s best for your baby.
If one breast keeps him sleeping 4 hours at night, there’s no need to switch. But if he seems hungry too often or he’s gaining weight too slowly, give 5 minutes on one side and then 10-15 minutes (or even longer) on the other. That way, your baby will get the foremilk from both breasts and still get all the hindmilk from the second side. (And any hindmilk left in the breast at the end of a feeding will stay there and just boost the calories of the next meal.)Interestingly, babies who eat formula sleep fine, despite there being absolutely zero difference between the first gulp of milk and the last. So, probably the foremilk/hindmilk issue isn’t that important.