You take a rectal temperature by placing a thermometer in your baby’s bottom. This method is more accurate than most other methods. But do this only when instructed by your baby’s doctor. Use the steps on this sheet as a guide.
Be sure to use a thermometer that is specifically designed for rectal use.
Remove the cover from the thermometer.
Wash the thermometer with warm soapy water; then rinse with clear water.
Wipe the thermometer dry or let it air dry.
Smear a bit of petroleum jelly or water-based lubricant on the tip.
Put your baby on his or her back on a firm surface.
Hold the baby’s ankles and lift both legs, as if changing a diaper.
Place your baby face down across your lap.
Use one hand to part the baby’s buttocks.
Follow the specific directions for using your digital thermometer.
Gently slip the tip of the thermometer into the rectum (the opening where bowel movements leave baby’s body), no farther than ¼ to ½ inch. Never insert the tip more than ½ inch.
Hold the thermometer in place until it beeps.
Slide the thermometer out. Read the temperature on the digital display. Normal rectal temperature is about 97.6°F (36.4 °C) to 100.2°F (37.9°C).
Before putting the thermometer away, clean it with soap and warm water.
Make a follow-up appointment as directed by our staff.
Call your doctor right away if your child has any of the following:
Bleeding from the area where you took the temperature
In an infant under 3 months old, a rectal temperature of 100.4°F (38.0°C) or higher
In a child of any age who has a temperature that rises repeatedly to 104°F (40.0°C) or higher
A fever that lasts more than 24-hours in a child under 2 years old, or for 3 days in a child 2 years or older
Your child has had a seizure
Your child seems very ill, is listless, or is acting very fussy