Can You Refuse To Allow A Rectal Temperature Check On An Infant? (5 Types Of Thermometers & How To Take Temperature By Age)

The simple answer is yes. If you are the guardian of an infant, you have the right to refuse a Rectal Temperature Check or any medical assessment. But before doing that, please note that a rectal temperature is used on infants because it is the most accurate way of doing so. There are other options, of course, but between the age of 0-3 months, it is the recommended way to get the most accurate temperature.

Different types of thermometers and how to use them

Various infant thermometers are shown that can be used via ear, forehead, or underarm.
  1. Oral thermometers (mouth) – This is ideal for alert babies. The body temperature can be obtained by placing the oral thermometer under the tongue toward the back of the mouth with the lips closed. Hot or cold liquids can alter the temperature reading, so it is advised to delay the temperature measurement by 10-15 minutes after consuming beverages.
  2. Axillary thermometers (underarm) – Considered to be one of the least accurate because they’re taken outside of the body rather than inside, it can be helpful to compare the result to ear, oral, and rectal temperature readings, which are more precise. Place the tip of the digital thermometer under their arm, with the tip gently pressed against the center of the armpit, and wait for the beep that indicates the reading is done.
  3. Rectal thermometers (rectum) – Has a similar bulb-like shape as an oral thermometer but usually has a shorter and stubbier tip for easier insertion into the rectum. The American Academy of Pediatrics (AAP) recommends using a rectal option for babies under 3 months old. Always clean the bulb before using it. Once cleaned, apply a small amount of lubricant like petroleum jelly on the tip. Place your baby on their back, lift their thighs or place your child on their belly on your lap or other firm surfaces. If you put your child’s belly down, put your hand against the lower back to hold the child in place. Insert the lubricated thermometer 1/2 to 1 inch into the rectum. Be gentle; there should not be any resistance. If there is, stop.
  4. Temporal thermometers artery (forehead) – Placed on the skin of your forehead with the sensor in the middle of your forehead to get your body temperature, it uses infrared technology to measure the heat energy your body gives off. Like the axillary thermometers, this may be less accurate than other types. Direct sunlight, cold temperatures, or a sweaty forehead can affect temperature readings. Variations in user technique, such as holding the scanner too far away from the forehead, also may affect accuracy.
  5. Tympanic thermometers (ear) – Digital ear thermometers use infrared sensors too in measuring the temperature inside the ear canal and can give accurate results within seconds when used correctly. First, gently insert the thermometer’s tip into the ear canal toward the eardrum. The sensor should be pointing down the ear canal and not at the wall of the ear. Once it’s in position, turn it on and wait for it to signal that the reading is complete.

Taking temperatures by age

Mom is checking her infant sons temperature via his ear

Newborn to 3 months

AAP (American Academy of Pediatrics) highly recommends a rectal thermometer to get the most accurate temperature within this age bracket.

New research suggests that a temporal artery thermometer might also provide accurate readings in newborns.

3 months to 4 years

By this age, you can take your child’s temperature using most of the possible ways (oral, axillary, temporal, and rectal) with the use of a digital thermometer.

Still, you might want to wait until your baby is at least 6 months old to use a digital ear thermometer.

If you doubt the result, the most accurate would still be the reading via rectal thermometers.

4 years and older

By 4 years and up, most kids can hold a digital thermometer under their armpits and tongue.

You can still use other thermometers, and the most accurate result would still be taking the temperature via rectal.


Can you hurt your baby by doing a rectal temperature check?

The possibility is always present, which is why it is advisable to have a professional do the procedure.

You can do it at home, but you need to keep in mind that there should be no resistance from the baby. If there is any, please do not force to do it and try a different way instead.

When is a rectal temperature check not allowed?

The rectal route is not allowed if the child has neutropenia, thrombocytopenia, a bleeding disorder, is preterm birth, or has had rectal or bowel surgery.

Tympanic (infrared) measurement is not recommended for children younger than 3 months.

What is the temperature of a baby with a fever?

Body temperatures

According to a study published via the National Library of Medicine, here are the average body temperatures based on age.


Our body’s temperature tells us a lot about what might be happening inside our system that we haven’t felt entirely yet. That’s why it is important to get the most accurate reading of our temperature.

This is particularly vital for newborn babies due to the significant change of temperature they have to go through from the mother’s womb, which is warm and cozy, to the outside world, which is not always comfortable even for us adults.

If your baby is feverish, low in energy, and is not eating the proper amount according to their age, please do not hesitate and contact your healthcare provider to get the best possible help as soon as possible.

Was this article helpful?

Currently located in the Philippines. Mother of an active curly boy whose energy rarely runs out. When I am not busy keeping up with my son, you'll find me reading, cooking, or most of the time keeping the house clean.

Leave a Comment