How to tell the difference between baby spit-up and vomit 

How can I tell whether my baby is just spitting up or is actually sick and vomiting? 

Most, if not all, babies will spit up once in a while, some until they’re a year old or even later. Most will stop spitting up frequently by the time they are sitting up—between six and nine months—as gravity keeps the milk in and the stomach muscles are stronger. The volume of the spit-up doesn’t really matter, but projectile vomit is concerning. This would involve the vomit travelling several inches or even feet across the room. If that happens just once in a while, it isn’t usually a problem, but if your baby has projectile vomiting after each and every feed, it warrants immediate medical attention to rule out an obstruction in the gastrointestinal tract (such as pyloric stenosis). So after a few rounds of projectile vomiting in a row, you should proceed to your nearest emergency room.If your child is growing well, taking the breast or bottle without issue and is not arching their back or showing other signs of pain during or after a feed, spitting up is rarely a concern. Pain or refusing the breast or bottle can indicate the spitting up is painful, which is a sign of gastroesophageal reflux disease or heartburn. If your baby is experiencing this, your paediatrician may weigh the pros and cons of prescribing a drug that reduces stomach acid to prevent the pain.

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