FRIDAY, Feb. 23 (HealthDay News) -- Over-wrapping infants, especially during the cold winter months when the flu and other infections are at their peak, can increase the risk of sudden infant death syndrome (SIDS), say experts from the Johns Hopkins Children's Center.

Sudden infant death syndrome (SIDS) is the leading cause of death in infants under one year of age.

Many parents and caregivers are not aware that over-wrapping, which can lead to thermal stress, is a risk factor for SIDS. And when over-wrapping is combined with infections and unsafe sleep positions -- two other risk factors for SIDS -- you have a recipe for disaster, Dr. Ann Halbower, director of the Children's Center Sleep Disorders Program at Johns Hopkins, said in a prepared statement.

"In my practice, I often find that new parents haven't been told about all the risk factors for SIDS, how to properly put their baby to sleep or that they should never over-swaddle," said Halbower. "It's a conversation that's just not happening often enough in pediatricians' offices."

It is widely known that placing babies to sleep on their backs is the safest position. But an alarming number of parents and caregivers are still putting babies to sleep face-down or in side-sleep positions, both of which are risk factors for SIDS.

"Several studies in inner cities have shown that many infants sleep with too many blankets or wraps on and in crowded beds with other family members," said Halbower.

And, Halbower said, parents should resist the urge to over-wrap their babies in the winter, when it is cold outside and infections are rampant.

"Babies who are sick need to vent off the heat from their fever, so bundling baby too warmly is possibly the worst thing you can do in this situation," she said.

To reduce the risk of SIDS, new parents should take these precautions:

• Place babies face up in the crib.
• Put babies' feet closer to the foot of the bed; this keeps babies from rolling down.
• Tuck in blankets at babies' feet; never tuck blankets in higher than the armpit.
• Never cover a baby's face or head, since infants release most of their extra body heat through their head.
• Never fall asleep with a baby on the couch, since you could roll over on or drop the baby.
• Don't allow a baby to share a bed with older siblings and/or parents; the baby can be kept in the parents' room, but only in his or her own crib.
• Don't rely on baby apnea monitors; These monitors can detect heart rhythm disturbances or lapses in breathing, but cannot pick up on drops in oxygen levels and other subtle changes leading up to SIDS.
• Keep in mind that premature babies are at higher risk for SIDS.

Talk with your pediatrician about risk factors for SIDS, Halbower said. Pediatricians should also make safe-sleep counseling a part of the regular well-baby exam right through an infant's first year of life.

More information

The National Institute of Child Health and Human Development has more about SIDS.