It's unpredictable. And it's messy. But laundry woes aside, spit–up usually isn't an issue. How can you tell when it's too much? And how is spit-up different from vomit? Let's find out.

What's Spit–up, and What Causes It?

Spit–up, also called reflux, is the flow of food from the stomach to the mouth. It's common, and might continue until your baby is a year old (but take heart — things are likely to improve during the second six months). Often, it's only the result of a developing digestive system or of overfeeding.

Spitting up can happen when your baby:

• Burps (this is called a wet burp)
• Eats too much
• Swallows too much air
• Is just having that kind of day (spit happens!)

There's no reason to worry about these common causes for spitting up. It's not painful, and most babies don't even realize they've done it. If your baby is healthy and gaining weight, it's just part of the development process.

Quantity Is the Key

It might seem like a lot, but the amount of liquid your baby spits up might not be as much as you think.

One tablespoon is normal, but it looks like a lot.

Two tablespoons also can be normal.

If your baby spits up more than this (or if spitting up is associated with respiratory symptoms such as choking, coughing, or wheezing), ask your health care professional if there's a reason to be concerned.

How Can You Lessen the Spit–up?

To help your baby spit up less often, try:

• Holding her in a more upright position while feeding
• Burping her every five to ten minutes while feeding
• Making sure the hole in your bottle's nipple isn't too large (for bottle-fed babies). If milk continues to drip out when you turn the bottle upside down, the hole is probably too large. Try replacing the nipple with one with a smaller hole.
• Keeping your baby in an upright position after eating. Lying flat on a full stomach can lead to spit-up.
• Avoiding too much activity immediately after feeding.
• Feeding your baby less food, but more often.

How Is Spit-up Different From Vomit?

If spitting up is making your baby uncomfortable, and gets more forceful with more volume than usual, it may be vomiting.

More volume might mean it's vomit.

When babies vomit more than once, it's usually caused by a virus and includes diarrhea. Although these viruses usually aren't dangerous, they can cause dehydration.

Because babies under 1 year old are at greater risk of dehydration, consult your health care professional immediately if you think your baby may be dehydrated.

When Should You Be Concerned?

Although it can set off alarm bells, an occasional vomiting episode usually isn't a reason to be concerned. Frequent vomiting can indicate reflux disease, intestinal obstruction, infection, or a protein allergy. Contact your health care professional if your baby's usual spit-up:

• Increases in volume or force
• Causes choking episodes or respiratory difficulty (wheezing or coughing)
• Leads to other issues (discomfort, fussiness, poor weight gain, or weight loss)
• Is accompanied by a fever, diarrhea, bloody mucus in the vomit, or a bloated abdomen
• Is green or yellow
• Is frequently projectile

Sometimes repeated vomiting in babies between 2 weeks old and 4 months old can be a sign of a blockage at the stomach. Contact your health care professional if your baby vomits repeatedly.

When babies have sudden bouts of vomiting associated with diarrhea, it's usually caused by a virus. Although these viruses usually aren't dangerous, they can lead to dehydration, which can be a serious problem. It's important to know the signs of dehydration and what you can do to prevent it.

• Has fewer wet diapers than normal
• Seems very tired or weak
• Has tearless, sunken eyes, dry skin, and little saliva

The younger your baby is, the greater the concern for dehydration. It's important that you replace the fluids your baby is losing with small, frequent feedings while she is ill. In many cases, an oral rehydration solution such as Pedialyte® is recommended. Check with your doctor or nurse for advice.