How To Dress Baby With Fever at Night (& When To Worry)

| Reviewed By Amanda Lundberg, BSN, RN

If infants have a high temperature, it is advised to dress them in one light layer of clothing. The best choices are 100% cotton pajamas or a cotton sleep sack, with only a diaper as an extra layer.

Avoid using swaddling blankets until their temperature starts to come down as this could risk overheating.

Most fevers are harmless and can be easily managed at home, but you should always be alert to signs of severe illness. 

Mount Sinai reminds parents to contact their babies’ doctor or head to the emergency room if:

  • Your child does not act alert or more comfortable when their fever goes down
  • Fever symptoms come back after they had gone away
  • The child does not make tears when crying
  • Your child does not have wet diapers or has not urinated in the past 8 hours
  • Is younger than age 3 months and has a rectal temperature of 100.4°F (38°C) or higher.
  • Is 3 to 12 months old and has a fever of 102.2°F (39°C) or higher.
  • Is under age 2 and has a fever that lasts longer than 48 hours.

How To Dress Baby With Fever at Night

Babies tend to sleep best when they are neither too hot nor too cold, so stick to dressing your little one in lightweight clothing if they have a fever.

This could be a diaper beneath a light, breathable cotton onesie or 100% cotton pajamas.

Avoid dressing them in beanies or heavy, high-TOG swaddles (even in winter), and instead, focus on maintaining a comfortable room temperature for them.

You can place socks on your little one’s feet if the room is cool to prevent chills.

Should You Swaddle a Baby With a Fever?

As swaddles can be quite warm and restrictive, perhaps wait until your little one’s temperature starts to drop.

You can then swaddle your baby in light material such as a cotton muslin blanket.

One mom on the Baby Center community forum shared that her feverish son slept swaddled comfortably in a muslin blanket with just a diaper beneath.

Should Baby Wear Sleep Sack With Fever?

If your baby has a fever, it’s advisable to dress them in one light layer of clothing and/or a sleep sack.

A diaper and a sleep sack or a diaper and a onesie is appropriate as too many layers may cause your baby discomfort.

Be sure to consider the TOG rating of their sleep sack in relation to room temperature too.

Fever in Babies: When To Worry

According to the Children’s Hospital of Philadelphia, it’s essential for babies older than 3 months to see a doctor if their fever is accompanied by any of the following:

  • A rash
  • Convulsion/seizure
  • Severe vomiting or diarrhea
  • Inconsolable crying
  • They are difficult to awaken
  • They’ve been in a hot place such as inside a hot car
  • Appearing/acting very sick
  • Your child is on steroids or has immune system concerns
  • They are not up to date with their vaccines

For babies between 2 and 3 months old, alert the doctor immediately to a rectal temperature higher than 100.4°F. Newborns under 2 months old with a temperature of 100.4°F should be taken to the emergency room.

Febrile Seizures

Febrile seizures in infants are convulsions or fits that can occur in response to a sudden spike in body temperature, often due to an infection.

They most commonly occur in children between the ages of 6 months and 5 years. 

Febrile seizures are usually brief, lasting for less than 5 minutes, and may involve twitching or jerking of limbs, loss of consciousness, and sometimes foaming at the mouth. 

While they can be frightening for parents to witness, febrile seizures are typically not harmful and do not cause long-term damage. 

However, it’s important to seek medical attention after a febrile seizure to determine the underlying cause and receive appropriate care.

Is Sleeping With a Fever Dangerous?

Allowing your little one as much sleep and rest as they need is a good thing, and though it won’t directly improve the fever itself, sleep can help their immune system fight off infection better.

Sleeping with a fever is fine (and is recommended to ensure the body gets the rest it needs) unless your child is a newborn or has underlying medical conditions.

Keep an eye out for when a fever could be a sign of something serious.

Ways To Take Your Baby’s Temperature

There are several methods for taking a baby’s temperature. Here are the five most common ways:

  • Rectal Temperature: This method involves inserting a thermometer gently into the baby’s rectum. It provides one of the most accurate readings, but it can be a bit uncomfortable for the baby.
  • Oral Temperature: Placing a thermometer under the baby’s tongue is another common method. This is suitable for older babies who can keep their mouths closed around the thermometer.
  • Axillary (Under the Armpit) Temperature: This method involves placing a thermometer under the baby’s armpit. It’s less invasive and generally comfortable for the baby, but it may not be as accurate as rectal or oral methods.
  • Forehead (Temporal Artery) Temperature: This involves using a special thermometer that scans the baby’s forehead or temporal artery. It’s non-invasive and quick, providing a fairly accurate reading.
  • Ear (Tympanic) Temperature: This method uses an infrared thermometer to measure the temperature inside the baby’s ear canal. It’s convenient and provides a quick reading, but it may not be as accurate as rectal or oral methods if not done correctly.

According to The American Academy of Pediatrics

“If your child is younger than 3 years old, a rectal temperature gives the best reading. At around 4 or 5, you can feel comfortable taking a temperature by mouth.”

Understanding What Is Considered a Fever in Babies

From newborn to 2 years old, a fever is considered a temperature of 100.4°F (38°C) from a rectal thermometer or 99°F (37.22°C) using an armpit thermometer.

Contact your healthcare provider if your baby is under 3 months and has a fever.

Should I Let My Child Sleep With a Fever?

Absolutely. Though it can be nerve-wracking, parents should allow feverish babies to rest and recover, so it’s more important to let them sleep than to monitor their temperature throughout the night.

An important exception is with babies under 2 months old.

It’s usually advisable to check your young infant’s fever every 2 to 4 hours, and consult your doctor immediately if their fever reaches 100.4°F or higher.

A young mother checking her baby's temperature with a concerned look on her face.

Does Sweating Mean Fever Is Breaking?

When a baby’s fever breaks, it means their body is successfully regulating its temperature back down to normal levels. 

This process often involves the body’s cooling mechanisms, which can include sweating.

Sweating is one of the ways the body naturally cools itself. When the body temperature is elevated due to a fever, the hypothalamus in the brain signals the sweat glands to produce sweat. 

As the sweat evaporates from the skin, it helps dissipate excess heat, which aids in lowering the body temperature.

So, when a baby’s fever breaks, it indicates that their body has effectively started to regain control over its temperature regulation.

Sweating is a positive sign that the fever is on its way down and the baby’s body is beginning to recover.

Do Fevers Usually Spike at Night?

It’s common for a fever to spike in the evening as body temperature naturally rises at night, so a fever that felt mild during the day can feel much stronger as we sleep.

You can help reduce the severity of your baby’s fever with a room-temperature bath and some formula/breast milk to keep them hydrated.

Causes of Fever in Babies

A fever in a baby can sometimes be a sign of a more serious underlying condition, especially if it’s accompanied by other concerning symptoms. 

If you’re ever unsure or concerned about your baby’s fever, it’s best to consult a healthcare professional for advice and guidance.

Common causes of fevers in babies include: 

  • Viruses like the common cold, influenza, and respiratory syncytial virus (RSV) can lead to fevers in babies.
  • Bacterial infections, such as urinary tract infections (UTIs), ear infections, and bacterial pneumonia, can cause fevers.
  • The process of teething can sometimes cause a slight increase in body temperature, although it’s usually not considered a true fever.
  • Vaccinations can occasionally lead to a mild fever as the body’s immune system responds to the antigens in the vaccine.
  • Bundling a baby up too warmly or keeping them in a hot environment can lead to an elevated body temperature.
  • Being in a hot environment, like a sunny room or a car without proper ventilation, can cause a baby’s body temperature to rise.
  • Some medications, particularly antibiotics, can cause a mild fever as a side effect.
  • Conditions like Kawasaki disease or autoimmune disorders can lead to persistent fevers in infants.
  • Meningitis is a serious infection of the membranes surrounding the brain and spinal cord that can cause a high fever.
  • Urinary tract infections (UTIs) are more common in girls and can lead to fever along with other symptoms like irritability and feeding difficulties.

When To Treat Baby Fever

A good rule of thumb is to treat your baby’s fever if it causes them discomfort — this normally applies to anything higher than a low-grade fever (100-102°F).

A high fever can cause your little one to feel pretty miserable with aches, sweating, and headaches, so it’s fine to administer appropriate medicine every few hours in the name of comfort.

Acetaminophen (Tylenol) and ibuprofen (Advil, Motrin) are the most effective for treating fever in babies and young children.

Just be sure to speak to your pediatrician before administering any medications.

How To Reduce Fever in Baby Naturally

Before reaching for the medicine cabinet, try some of these simple and natural methods for managing your little one’s fever:

Give Them a Bath

The American Academy of Pediatrics (AAP) in association with Kinsa Health heartily recommends bathing feverish babies before bed.

It can be a regular soak or sponge bath — just be sure to use lukewarm water for a temperature over 100.4°F, and avoid cold or ice baths.

If your little one starts to shiver, end bath time, and dress them in lightweight cotton pajamas.

Provide Plenty of Fluids

Keep your baby well hydrated to bring their fever down.

If they’re still breastfeeding, simply continue to feed as often as they need, and if they’re on solids, offer them plenty of water, diluted fruit juice, yogurts, popsicles, or an electrolyte solution.

Keep Your Baby at Home

Last but not least, keep your little one home to rest and recover as they could be contagious.

Keeping your baby at home with you allows you to provide them with a little extra TLC — extra cuddles and play if they’re up to it!