Why Do Babies Spit Up? And What You Can Do About It

Learn why babies spit up, how to respond if baby seems to spit up more frequently, and how to tell when baby’s spitting isn’t normal.

All babies spit up at some point. And most of the time, spitting up is normal. But what if baby starts spitting up more often --- or the spit-up turns forceful? Today, we’ll cover why babies spit up, and how to respond if baby seems to spit up more frequently. We’ll also highlight how to tell when baby’s spitting isn’t normal, with signs that could point to a more serious problem.

Why do babies spit up?

Usually, babies spit up breastmilk or formula very frequently in the first three months of life.

This is because the valve in their esophagus isn’t fully developed. The valve is known as the esophageal sphincter muscle. It’s a muscle ring that sits between the bottom of the esophagus and stomach, and it’s meant to keep food that’s moved into the stomach from flowing back up into the esophagus.

But when baby’s stomach gets too full, or when you change their position too quickly right after you feed them, the contents of the stomach force the sphincter open. When this happens, the stomach contents end up flowing back through baby’s esophagus --- and out their mouth.

This is spit up, which is also called infant reflux. And it’s completely normal, so you don’t need to take any action.

Usually, with reflux, baby will just spit up a little at a time. Even if baby spits up frequently --- after most, or even all, feedings --- there’s no reason to be concerned as long as baby seems content and the spit-up flows out gently. In other words, as long as baby is a “happy spitter,” everything is fine.

As baby grows and their esophageal valve develops more fully, baby will spit up less and less. If baby develops normally, they’ll grow out of their spitting up within their first year of life (usually, some time after 6 months of age).

Learn more about baby spit up from What To Expect:

What else can cause spit up? What can I do about it?

An overly full stomach and a sudden position change are the most common causes of spitting up, caused by the esophageal sphincter’s failure to close reliably.

But other common causes of spitting up can be remedied so your baby spits up less frequently. Here are some of the most common causes, along with what you can do to reduce spit up.

Head is not kept upright

One position change that could lead to spit up is if baby’s head isn’t kept upright for long enough after a feed.

What to do?: Keep baby’s head upright and elevated for at least 30 minutes after feeding. Make sure their head stays higher than their stomach. Don’t lay them down right away to change their diaper, to have them nap, or to give them playtime on their stomach or back.

Improper feeding position

If you don’t have baby positioned properly for a feeding, they may gulp down too much air during a feeding. This will cause gas, and cause baby to gulp their feedings along with them spitting up. This isn’t serious, but it is uncomfortable for baby.

What to do?

The way to remedy this is simple --- make sure baby is in the proper position during a feed. Baby might spit up because they aren’t comfortable in the position you chose before.


Overeating can also lead baby to swallow air and spit up more. This can lead to crying, gas, and stomach discomfort as well.

What to do?

If you’re feeding and see baby exhibit signs of fullness (like turning away from the bottle or breast), it’s time to end the feed. Don’t force them to eat more.

Burping them during and after each feed will also help release excess air that they’ve swallowed.

Remember, though, that baby may also overeat on their own without swallowing air, and without realizing it. This simply leads to backflow into the esophagus and spitting up as a result. There’s nothing you can do about this, so just be patient as baby’s digestive system develops.

Eating too quickly and swallowing air

Baby may also gulp down too much air, and spit up, because they’re eating too quickly. This could be caused by a bottle with too fast of a flow. Or, if you’re breastfeeding, you could have an especially abundant milk supply or a strong let-down reflex (where more milk flows more quickly from the breast to baby’s mouth).

What to do?

Remove air caused by eating too quickly, and help slow down feeds so baby takes in less air in the first place.

  • Burping baby during and after every feed is helpful.
  • You might also consider feeding baby more frequently throughout the day, because if they go into a feed too hungry, they might try to drink too quickly.
  • If you’re breastfeeding and suspect a strong let-down, try pumping some breastmilk before a feed to slow down the flow for when baby starts to eat.
    • You could also try nursing in a reclined position to lessen gravity’s effects.
  • And if you’re bottle feeding, think about switching to a bottle with a slower flow.
    • Also, make sure the bottle you use has an anti-colic valve, meant to keep baby from swallowing too much air during a feed.

Difficulty latching due to engorgement

If you’re breastfeeding and are experiencing engorgement (over-full breasts), your breasts may become too hard. This may cause baby to struggle to latch onto your breast properly, swallow too much air, and spit up as a result.

What to do?

Soften the areola (the area around the nipple) by removing some milk, so baby will be able to latch more effectively. Use a breast pump on a low setting, or express a little milk by hand.


Another reason baby may spit up after a meal is if they’re overstimulated. If you play or bounce them too soon after a meal, and they spit up, it’s likely due to overstimulation. Again, this isn’t serious, but could be uncomfortable for babies.

What to do?

If you notice that baby spits up after a post-meal play session, plan to keep baby calm right after feeding them. Wait at least 20 minutes after future feeds before bouncing them or engaging in other active play.

When should I be concerned about spit up?

Normal spit-up is gentle, not forceful --- it easily flows out of baby’s mouth. And when spitting up normally, baby will seem happy and content. Baby will maintain or gain weight effectively when they’re spitting up normally. But if baby spits up in a forceful or projectile manner, and seems distressed in the process, this isn’t normal spit-up. This is vomiting, and this is a cause for concern.

If you notice that your baby is vomiting often, has periods of vomiting lasting over 24 hours, or vomiting along with any of these symptoms, call your pediatrician immediately. This could be a sign of something serious:

  • Muscle contractions
  • Weight loss
  • Visible distress or appearance of being in pain
  • Blood in the vomit or spit-up
  • Green or yellow color of vomit
  • Failure to thrive
  • Unwillingness to eat
  • Choking
  • Dehydration

Vomiting could be caused by an illness or infection. It could also be caused by one of these conditions that requires medical attention:

Regardless of if your baby is vomiting, you should also contact your pediatrician if frequent spitting up persists past baby’s first birthday. Fewer than 10% of babies still spit up regularly after one year of age. If baby keeps spitting up past the one-year mark, they could have an allergy or GI issue.

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All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

These statements have not been evaluated by the Food and Drug Administration. Products are not intended to diagnose, treat, cure or prevent any disease.  If your infant has severe eczema, check with your infant’s healthcare provider before feeding foods containing ground peanuts.