Why Your Baby Spits Up (And When You Should Actually Worry)

Spit-up is one of the most confusing newborn concerns. Parents often associate spit-up with reflux or illness, but most spit-up is normal and tied to immature digestive systems. Babies have a loose esophageal sphincter—the muscle that keeps milk down—so when their tummy fills or pressure changes, milk easily escapes.

Overfeeding, fast flow bottles, swallowing air, or laying flat too soon after feeding all increase spit-up. A baby feeding quickly may gulp more than their system can comfortably hold. A baby fed in a reclined position may lose control of pacing. Babies also spit up more when overstimulated because their digestive system works less efficiently when their body is in a heightened state.

What matters most is your baby’s behavior, not the volume. A baby who spits up but is content, gaining weight, and feeding comfortably is experiencing normal spit-up. A baby who cries during feeds, arches intensely, refuses the bottle, or has weight concerns needs more guidance.

Burping during the feed, using paced feeding, keeping your baby upright afterward, and ensuring the flow rate is slow and manageable reduce spit-up drastically.