Fever, a higher-than-normal body temperature, is often considered the first indicator for most illnesses affecting babies. It is the fundamental clue that the immune system is working to fight an infection. Accurate body temperature measurement is vital, especially for infants, as small differences in temperature readings can determine whether or not the baby needs to be hospitalized for thorough medical examination. There are several ways of taking the baby’s temperature: by mouth, by ear, on the forehead, under the arm, or rectally (in your baby’s bottom). However, the American Academy of Pediatrics (AAP), Consumer Reports, and the American Academy of Family Physicians consider rectal readings, obtained using the digital rectal thermometer, to be the most precise way to take a temperature in infants and children under the age of three.

The normal body temperature is approximately 98.6 degrees Fahrenheit (or 37 degrees Celsius) when taken orally and 99.6 degrees Fahrenheit (or 37.5 degrees Celsius) when taken rectally (inserted into the anus).  Oral temperatures above 99.5°F (37.5°C) or rectal temperature readings above 100.4°F (38°C) are considered as fever by many doctors.

Until recently, there were 2 variants of the rectal thermometer: digital (plastic) rectal thermometer and the old-fashioned mercury-in-glass rectal thermometer.Due to the toxic risks of mercury, in the event of a breakage of the glass, the use of the mercury-in-glass thermometer has been discontinued. The AAP now considers them unsafe for use, and advises people who still have these mercury-rectal-thermometers to liaise with their doctors to dispose of them properly.

In addition to not containing any toxic solution, the digital rectal thermometer comes with other useful features and functions. They give fast readings, which means you can get the job done within 10 to 60 seconds. To prevent over-insertion, most baby rectal thermometers have an indicator or design which makes it easy to know when the proper position is obtained. The Start button and LCD (digital readout) in some of the models make it easy to start and read the temperature. Last but not least is the option to recall the last temperature readings.

Tips on using a Rectal Thermometer

•    For best results, for 15-20 minutes prior to use, the child should avoid eating or drinking any liquids, physical activity, or bathing.
•    Clean only the sensor area of the thermometer by washing with soap and warm water or rubbing alcohol (e.g. 70% isopropyl alcohol) before and after use, and lubricate the tip with a small amount of jelly (check the recommendation for your model) to ease insertion before use.
•    Position the child properly: lay baby on his/her stomach with legs hanging down, either across your knees or at the edge of a bed or changing table.
•    Gently insert the tip of the thermometer into the baby’s rectum (following the instruction for your model). Most digital rectal thermometers have features (beep, guard, etc) to prevent over-insertion. Stop if you detect resistance.
•    Allow enough time for an accurate reading, usually 10 to 60 seconds, (follow your model recommendations), gently remove the thermometer, and then check the results.
•    Clean as instructed and store properly.

You can find links to the most popular and bestselling baby digital rectal thermometers on our site. Feel free to use the links to find out more info and follow the instructions for your particular model. High, prolonged fever requires urgent medical attention, especially for infants. Always contact your pediatrician. Thank you for visiting us today.