Taking Your Baby's Temperature
If a traditional thermometer breaks, there is a risk of mercury poisoning, so we recommend new parents use a digital thermometer. When taking your baby’s temperature, gently hold your infant still, leave the digital thermometer in place for the length of time recommended by the manufacturer, and clean it according to the provided directions.
Oral temperature: This method is not used for babies.
Underarm temperature: A normal temperature range is 97.7 to 99.5 degrees Fahrenheit. This is the recommended method for any child under four years old. To properly take an underarm temperature, make sure your baby’s armpit is dry and free of clothing. Place the thermometer tip high in your baby’s armpit, and hold your child’s arm snugly against the body until the proper amount of time has elapsed.
Rectal temperature: The normal temperature range is 98 to 100.4 degrees Fahrenheit. Lubricate your thermometer bulb with petroleum jelly, place your infant on his or her stomach, and spread the buttocks so the anus is easily seen. Slowly and gently insert the tip of the thermometer into the anus slightly less than one inch, so the tip is no longer visible. Hold the thermometer in place for the length of time recommended by the manufacturer.