Baby spit up vs vomit: What’s the difference? | Expert advice

Last Updated on May 22, 2023

Some parents might be wondering what the difference is between spit-up and vomit. Spit up is a baby’s stomach contents flowing easily through their mouth, perhaps with a burp. Vomiting occurs with a forceful flow that shoots out inches rather than trickling from the mouth. Here, we’ll go through what causes a newborn to spit up and vomit, as well as how to prevent it and when it might be a sign of a severe issue.

Baby Spit Up Vs Vomit: What's The Difference? | Expert Advice
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What is spitting up in infants?

The stomach contents flow back into the esophagus (the food pipe or tube that transports food from the mouth to the stomach) is known as spitting up. It is very common in healthy infants. People also call it acid reflux or gastroesophageal reflux, which occurs throughout the first six months of a baby’s life.  

Normally, a muscle known as the lower esophageal sphincter keeps food in the stomach where it belongs. Spitting up can happen to babies until this muscle matures, especially when they are full.

It doesn’t usually require any treatment. When your baby is between the ages of 12 and 14 months, their digestive system matures, allowing the problem to go away on its own.

We also have a guide on can babies choke on vomit while sleeping? You may also read it for further information.

What causes an infant to spit up?

What causes an infant to spit up?
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The leading cause of an infant spitting up is its small tummy size. When a baby is born, its tummy size is like a small marble. After 3 days, the tummy size is like a ping pong ball, yet it can’t contain much.

The little tummy can accommodate a sheer amount of milk until the baby is around four months old. Excess milk during feedings can cause your infant to spit up or be fussy.

Another reason for spitting up is gastroesophageal reflux or acid reflux. This means that when your baby’s lower esophageal sphincter isn’t fully closed due to less developed muscles in the upper esophagus, it allows fluids from their stomach to flow back into their esophagus when they are fed. 

Spit-up should be regarded as a regular part of your baby’s development, as long as they are in good health and growing weight.

How much does a baby spit up?

How much does a baby spit up?
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When it’s on your shirt, it may appear to be a lot, but the quantity of liquid your baby spits up isn’t as much as you believe. It’s generally only 1 or 2 tablespoons at a time. If your kid spits up more than this – or if his spitting up is caused by respiratory problems like choking, coughing, or wheezing, you should ask your pediatrician.

What are some ways to prevent spit-up?

Considerful feeding is the most effective method to help your baby spit up less frequently. Here are a few suggestions if you want to help your child spit up less regularly:

  • Hold the infant upright while feeding him.
  • After every 1 or 2 ounces of feeding, you should burb the infant.
  • If you’re bottle-feeding your infant, be careful not to use a nipple that is too large. If milk spills out when you turn the bottle upside down, try using a smaller nipple.
  • After eating, keep your baby upright. Spit-up can occur when he is laid flat on a full stomach.
  • Too much activity for your baby right after he eats may cause spitting-up.
  • Feed your baby less food, but more frequently.

What is vomiting in infants?

Vomiting is the forceful ejection of stomach contents through the mouth. Vomiting happens when the abdominal muscles and diaphragm tighten strongly while the stomach is relaxed. Typically, vomiting happens after feeding, but it can also occur during or between feedings in some babies.

There are two types of vomiting, including:

  • Reflux vomiting- tends to contain curdled milk due to poor digestion and may contain blood if vomiting becomes severe.
  • Non-reflux vomiting– tends to be more forceful and contains mostly bile (which is green) and partially digested food.

What causes vomiting In Babies?

What causes vomiting In Babies
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Vomiting can be caused by a large number of conditions, including gastroenteritis, pyloric stenosis, GERD, gastritis, food poisoning, intestinal obstruction, diabetes mellitus with ketoacidosis, viral gastroenteritis (influenza or rotavirus), irritable bowel syndrome (IBS), hiatal hernia causing diaphragmatic hernia (the esophagus passes through an abnormality in the diaphragm known as Bochdalek’s hernia), and liver cirrhosis.

Infant vomiting can also be a symptom of milk protein allergy, lactose intolerance, obesity, food poisoning from outside the home, cytomegalovirus infection, croup or other lower airway infections, or severe intestinal problems such as necrotizing enter-colitis or intussusception.

Vomiting occurs in about 50% of infants by the time they are three months old. It is more common with boys than girls, and vomiting is rare after six months of age.

Additionally, vomiting becomes less frequent as children become older – in one study, it was reported that nearly 80% of 18-month-olds still spit up some milk when vomiting, but only 5% did so once per week or more often.

If vomiting occurs after feeding, you should consult your doctor immediately because it can lead to dehydration which can cause serious health problems or death. On the other hand, if spitting up repeatedly happens after feeding and it bothers you, talk with your pediatrician about what might be causing the problem and how they treat your condition. 

Here are two different things that can happen to infants:

Vomiting involves throwing up mucus or food from one’s stomach out of the body via the mouth due to a vomiting reflex fit caused by irritation in the vomiting center of one’s brain. On the other hand, spitting up is an overflow of milk through the baby’s mouth.

Is spitting-up a symptom of an underlying condition?

If your baby’s spitting up a lot or recently, look for the following symptoms. If you notice any of these indicators, it’s important to contact your child’s doctor right away:

  • Isn’t gaining weight 
  • Spits up forcefully 
  • Spits up green or yellow fluid 
  • Spits up blood or coffee-like particles. 
  • Frequently refuses feedings 
  • Blood has been discovered in the stool 
  • Signs of poor health or respiratory issues 
  • Starts spitting up at age 6 months or older 
  • Cries for more than three hours a day and is more temperamental than usual
  • Fewer wet diapers than usual 

Feeding techniques might be helpful in some situations. In other cases, a doctor may prescribe medication to treat reflux.


  1. Caring for Your Baby and Young Child: Birth to Age 5 (Copyright © 2009 American Academy of Pediatrics)
  2. Spangler AK, et al. J Hum Lact. 2008;24(2):199-205
  3. Behrman RE, et al. Nelson Textbook of Pediatrics. 16th ed. Philadelphia: WB Saunders Co; 2000:165.
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Jenny lord

Jenny Lord, MSN, RN is a certified nurse and mother of three children William (11), Phoebe (10) and Daniel (6). She has worked in the healthcare industry for over 9 years. She has done her undergraduate degree from Canterbury Christ Church University and worked as a Nurse at Maidstone & Tunbridge Wells NHS Trust. Jenny is also a former Midwife, so she understands that experience can be very different in the hospital environment than what you may have heard or read about childbirth. Read more

Dr. Leah Alexander

Dr. Leah Alexander is a board-certified general pediatrician and has been practicing pediatrics at Elizabeth Pediatric Group of New Jersey since 2000. Since 2005, she has been working as an independently contracted pediatrician with Medical Doctors Associates at Pediatricare Associates of New Jersey. She also enjoys cooking outside of the medical profession. Read more

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