The hypothalamus, located in the brain, knows the right temperature for your toddler's body and sets his internal "thermostat" accordingly. Adult and child body temperatures usually stay around 98.6° F, but this can vary slightly depending upon a number of factors including the time of day, the temperature of the room or your toddler's activity level. When illness occurs, the hypothalamus will elevate your child's temperature to help him fight off the infection. Knowing your child's normal body temperature can help you determine when he has an infection or other type of illness that needs medical attention.
The American Academy of Pediatrics, or AAP, states that the average body temperature for healthy toddlers ranges between 96.8° F and 100.3° F if taken rectally and 95.8° F to 99.4° if taken orally. Body temperature fluctuates throughout the day, so your child's temperature might start out low in the morning and peak in the late afternoon.
Normal Body Temperature Rectal Method
The way you take your child's temperature -- orally, rectally or axillary -- can play a role in determining what is normal. Since toddlers can rarely hold the thermometers still in their mouths long enough to get a clear reading, taking temperatures rectally gives the most accurate results in children 3 or under. The average body temperature of a toddler when taken rectally is 98.6° F.
Normal Body Temperature Axillary and Oral Methods
The axillary method, in which you measure your child's temperature by placing the digital thermometer under her arm, can help you evaluate whether her temperature is normal or elevated. A reading of 99° or higher can indicate a fever using this method. This method often works well with active toddlers since it can be done quickly, but the AAP cautions that it is not as accurate as the oral or rectal methods.
When your child reaches 4 or 5, you can take her temperature orally. The average oral temperature of a healthy toddler is 97.6° F.
Taking a hot bath, being bundled in warm clothes or blankets, throwing a temper tantrum or playing outside on a hot day can all elevate your child's normal body temperature. To ensure accurate results, wait about 20 minutes before taking his temperature to give it time to return to normal.
Teething during the toddler years can often cause a slightly elevated body temperature -- rarely above 100° F -- that some people refer to as a "low-grade fever." The AAP stresses that temperatures between 98.7° and 100° F are not fever, but instead, variations of normal body temperature that do not indicate illness or infection. Discuss any concerns relating to your child's temperature with her doctor.