As I learned, babies sometimes wake up sweaty. We all perspire during the transitions between different sleep stages, but infants sweat more because their sleep cycles are shorter, says Dr. Wible. Since your infant's head is his largest body part, it's where the most heat is lost; this may cause his forehead and hair to be damper than the rest of the body. Of course, babies can also get sweaty when they're too hot and their body is trying to cool down. To make sure your child doesn't overheat while he sleeps, keep his room between 60? and 70?F, and dress him the way you would be comfortable without covers. Call the pediatrician if he has a fever or another sign of sickness, such as lethargy. By 3 or 4 months, when their sleep cycles are longer, many babies won't sweat as much. Others, though, like my son, are just sweaty sleepers and continue to be into their toddler years and beyond. A good tip: To prevent overheating, avoid blankets and hats while baby's sleeping.
Originally published in the April 2011 issue of Parents magazine.