Once your baby latches on and forms a seal, even more reflexes take over. There is a four fold system that allows your baby to transfer milk out of your breast like a perfect extracting machine. It may seem complex, but you and your baby are hard wired to function this way.
- Suck/swallow reflex- When the roof of your baby’s mouth is filled with breast tissue, the suck/swallow reflex is elicited. It has three components:
- Compression – the tip of your baby’s tongue lifts up to compress your breast tissue against the roof of his mouth.
- Retraction – the back of his tongue rolls backwards against your breast tissue toward your nipple, where the milk comes out (like pressing a tube of toothpaste toward the opening).
- Vacuum – his jaw pulls down, away from the roof of his mouth, creating a vacuum in the back of his throat to pull milk out of the breast, much like a breast pump.
- Letdown – After a few seconds of non painful nursing (up to a minute), your brain secretes the hormone, oxytocin, that actually makes your breast push the milk out. The first letdown pushes half of the stored milk out nursing breast, making it even easier for your baby to get it.
NOTE: If your baby cannot gape widely and you are having pain when your baby latches or nurses, this system will not function correctly. Your baby will compress your nipple, not the breast tissue, and resulting in less milk transfer. And the pain you feel will cause your brain to release a hormone, called cortisol. Cortisol is a stress hormone that makes your breasts hold onto the milk and can actually create postpartum depression.