Fever in the First 90 Days

Fevers in children seem to cause caregivers a great deal of anxiety. This stems from two factors. The first, is that fevers are frequently uncomfortable. If you can remember the last time you had a fever, I’m sure you would agree. You have no energy. Your muscles ache and your head hurts. You don’t want to eat or drink anything, and you can’t sleep. This happens with children as well, and it worries caregivers to see them so miserable. The second, is that there are a great deal of inaccuracies and myths suggesting that fevers are dangerous. The truth, however, is that fevers are not dangerous, even when they are very high. They simply tell us there is an infection. In children 3 months and older, what really matters is that they are responsive, hydrated, and breathing comfortably.

In children younger than 3 months, it’s a different story. Before 3 months of life, a fever must be discussed with a medical provider. The fever itself is still not dangerous. The concern is that their immature immune systems may have contracted a potentially life-threatening bacterial infection, which could be hiding in the blood, lungs, urinary system, or even the spinal fluid.

The provider may need to send these babies to the emergency department, where the work-up can include blood and urine cultures, or a spinal tap looking for meningitis. Because so much is riding on the temperature, you should follow different recommendations if your baby is younger than 3 months old.

Rectal Temperature

We must have the most accurate reading possible, and research shows that other methods are less reliable and accurate. For this reason, the only way to take a temperature in a child younger than 3 months old is rectally. Here are some examples of reliable, digital rectal thermometers for babies.

Only If You’re Worried

Avoid taking the temperature unless your baby is doing something new that worries you. For example, if they won’t stop crying no matter what you do, or they stop feeding or peeing normal amounts. These are good reasons to take the rectal temperature. Feeling warm is not a reason to check the temperature if nothing else is concerning. Neither is checking once a day or every few hours because this was done in the delivery hospital.

Numbers to Know

100.4ºF - any rectal temperature 100.4ºF or higher is a fever. This is the case for anyone, regardless of age.

97ºF - any rectal temperature below 97ºF is the same as a fever if your child is younger than 3 months of age.

What to Do

If your child is younger than 3 months of age, has a rectal temperature 100.4F and higher or less than 97ºF, and you checked it because you were worried, you must contact a medical provider immediately.