Sudden infant death syndrome

Sudden infant death syndrome (SIDS) is the unexplained death of a baby under 1 year of age while sleeping. SIDS can happen without warning to a baby who seems healthy.

SIDS is the leading cause of death in babies between 1 month and 1 year old. Most SIDS cases happen in babies between 2 and 4 months old.

SIDS is sometimes called crib death. Cribs don’t cause SIDS, but other sleep issues can increase your baby’s risk for SIDS.

What causes SIDS?

We don’t know what causes SIDS. But some things can put babies at higher risk of SIDS than others, including:

Sleeping

  • Sleeping on his tummy or on his side
  • Sleeping on pillows, soft surfaces or soft bedding
  • Wearing too many clothes to sleep or sleeping in a room that is too hot. These things can cause your baby to overheat.
  • Co-sleeping. This means that your baby sleeps with you in your bed. Half of all babies who die of SIDS are babies who share a bed, sofa or sofa chair with another person.

Individual characteristics

Can you lower your baby’s risk of SIDS and other sleep-related dangers?

Yes. Use these tips to help keep your baby safe during sleep.

Are there any products that can lower your baby’s risk of SIDS?

No. The American Academy of Pediatrics (AAP) doesn’t recommend using products, like special mattresses or wedges, aimed at reducing the risk of SIDS. There is no evidence that these products reduce the risk of SIDS or suffocation.

For more information

First Candle/SIDS Alliance
National Sudden and Unexpected Infant/Child Death and Pregnancy Loss Resource Center
The Compassionate Friends

Last reviewed March 2012

See also: Co-sleeping, Putting your baby to sleep, Safe sleep for your baby, From hurt to healing

Most common questions

How can I soothe my baby if she has colic?

About 1 in 5 babies develops colic - usually between 1 and 4 months of age. They cry constantly, often extending or pulling up their legs or passing gas. Sometimes their tummies are enlarged with air and gas from crying. There's no one cause of colic, but there are many different ways to ease your baby's discomfort. One way is to walk her in a soft-sided baby carrier that you strap to the front of your body. You can also try laying her tummy-down across your knees and gently rubbing her back. The pressure against her tummy may relieve her discomfort. Breastfeeding moms can ask their baby's health care providers about a change in food choices or eliminating specific foods that may cause your baby's colic. Keep in mind that colic usually disappears by 4 months of age, no matter what treatments you try.


How should I take my baby’s temperature?

If your child is younger than 3 years, taking a rectal temperature gives the best reading. Here's how:

  • Clean the end of a digital thermometer with rubbing alcohol or soap and water. Rinse it with cool water.
  • Put a small amount of petroleum jelly on the end.
  • Place your child belly down across your lap or on a firm surface. Put your palm against his lower back, just above his bottom. Or place your child face up and bend his legs to his chest. Rest your free hand against the back of the thighs.
  • With the other hand, turn the thermometer on and insert it 1/2 inch to 1 inch into the anal opening. Don’t insert it too far. Hold the thermometer in place loosely with two fingers, keeping your hand cupped around your child's bottom, until you hear the beep. Remove it and check reading.

What do I do if my baby is constipated?

Your baby's bowel moments depend on her age and eating habits. Every baby is different. Some babies have a bowel movement right after each feeding. Others have it only once a day. It also is normal that a breastfed baby (3 to 6 weeks of age) passes stools only once a week. Formula fed babies should pass stools at least once a day. If your baby is having irregular bowel movements but her stools are soft (no firmer than peanut butter), this isn't a sign of constipation. But if your baby's stools are firm, she seems fussy or cries when having a bowel movement, she might be constipated. Talk to your baby's health care provider.

©2013 March of Dimes Foundation. The March of Dimes is a non-profit organization recognized as tax-exempt under Internal Revenue Code section 501(c)(3).