Does your baby spit up after every feeding? Although it's messy, you probably don't need to worry. Spitting up rarely signifies a serious problem. As long as your baby seems healthy and is gaining weight, there's little cause for concern.

If you keep a burp cloth within reach at all times, you're in good company. Nearly every baby spits up occasionally. An estimated 40 percent of infants spit up on a regular basis.

Normally, a valve between the esophagus and the stomach keeps stomach contents where they belong. Until this valve has time to mature, spitting up may be an issue — especially if your baby eats too much or swallows too much air during a feeding.

Minimal spitting up doesn't hurt. It's not likely to cause coughing, choking or discomfort — even during sleep. Chances are, your baby won't even notice the fluid dripping out of his or her mouth.

Breast-fed babies tend to spit up less than bottle-fed babies do, perhaps because they're less likely to overeat and swallow excess air during feedings. Most babies outgrow this problem by the time they begin to sit and eat solid foods, often within six months to a year.

Although it may be impossible to prevent spitting up entirely, these tips may help:

• Keep it calm. Make each feeding peaceful and relaxed. Feed your baby before he or she becomes frantic.
• Sit up. Feed your baby in an upright position. Follow each feeding with 15 to 30 minutes in a sitting position. Try a front pack, backpack or infant seat. Gravity can help stomach contents stay where they belong. Be careful not to jostle or jiggle your baby while the food is settling.
• Take time to burp. Frequent burps during and after each feeding can keep air from building up in your baby's stomach. Sit your baby upright, supporting his or her head with your hand. Avoid burping your baby over your shoulder, which may put pressure on your baby's abdomen.
• Check the nipple. If you're using a bottle, make sure the hole in the nipple is the right size. If it's too large, the milk will flow too fast. If it's too small, your baby may get frustrated and gulp air. A nipple that's the right size will allow a few drops of milk to fall out when you hold the bottle upside down.
• Try smaller feedings. Feed your baby an ounce less than usual or limit nursing sessions to just one breast.

Normal spitting up doesn't interfere with a baby's growth or well-being. Contact your baby's doctor if your baby:

• Isn't gaining weight
• Spits up forcefully, so that stomach contents shoot out of his or her mouth
• Spits up excessively (more than a tablespoon or two)
• Seems hungry between feedings
• Has fewer wet diapers than normal or appears lethargic
• Has other signs of illness, such as fever, diarrhea or difficulty breathing
• Spits up green or brown fluid

Treatment will depend on what's causing the problem. More careful feeding techniques are often helpful. In other cases, medication to treat reflux or a procedure to loosen the valve at the bottom of the stomach may be recommended.