Out of all the times you might experience a fever, pregnancy is one of the most dangerous.
Having a fever during pregnancy may heighten your baby’s risk of birth defects, autism, and even pediatric infections. But why and what can you do about it?
In this article, we’re diving into the research on fever and pregnancy.
What is a Pregnant Fever?
A fever is a raised body temperature of:
- 3F (37.4C) or higher if taken from the armpit or forehead
- 4F (38C) or higher if taken by mouth
- 101F (38.3C) or higher if taken by ear or rectum
*Fever ranges are different for children
A fever may take several forms:
- Constant fever. A fever that holds the same raised temperature throughout the day.
- Intermittent fever. Temperature that goes back and forth between normal and a fever.
- Remittent fever. A fever varying between different raised temperatures.
When you get a fever, it usually means your body is fighting some type of infection. That infection could be caused by:
- Urinary Tract Infection (UTI)
- Ear infections
- Lung infections
- Throat infections
- Food poisoning (you’re more susceptible to food poisoning during pregnancy. Read: Lunch Meat and Pregnancy: Is It Safe? Precautions + Hacks)
Most fevers caused by a virus last 1-4 days.
Fevers may also be caused by other conditions, like rheumatoid arthritis, cancer, or heat exhaustion.
Typically, a fever is a normal part of getting sick and should go away on its own. During pregnancy; however, fever poses a bigger risk to your baby. Pregnant fevers should be reported to your doctor, treated seriously, and closely monitored.
Despite this, fevers during pregnancy aren’t uncommon and don’t usually lead to adverse outcomes if monitored.
Pregnant Fever Symptoms
The only way to know whether you have a fever is to take your temperature.
Without taking your temperature, you can’t definitively say you have a fever. However, there might be other pregnant fever symptoms, like:
- Forehead feeling hot to the touch
- Muscle aches
- Appetite loss
- Dark urine
How To Take Your Temperature
If you think you have a fever, or if you’re sick, take your temperature using a thermometer.
Here’s how to use the trusted DuoSmart thermometer to take your temperature by ear.
- Take the cap off the thermometer
- Press On
- Gently place thermometer end into the ear
- When reading is complete, take out of ear and view temperature
- Press Off
- Clean tip and place cap on for next use
- *Recommended: Pair your DuoSmart Thermometer with Bluetooth. This way, you can store up to 12 temperature readings in each mode to monitor your health.
If you have a pregnant fever, contact your doctor. Many fevers are caused by an illness that needs to be treated. For example, your doctor may recommend antibiotics to cure the illness that underlays your fever. In other cases, your doctor may suggest you take acetaminophen and monitor your fever to ensure it doesn’t get worse and improves over the next hours or days.
Bottom line: You can’t be sure what’s causing your fever (and what will treat it) until you contact your doctor.
Learn more by reading: Pregnant With Fever? Here’s Why & What To Do Next
The Best Thermometer in Pregnancy
If you think you’re pregnant with a fever, we recommend using the DuoSmart Thermometer. It’s the fastest and most versatile thermometer on the market for pregnancy and new families. Here’s a few more reasons why people love DuoSmart:
- Perfect for the family: can take temperature by ear, forehead, or non-contact mode
- Non-contact mode perfect for fussy children
- Option to connect to app allows you to store readings for all family members
- Suitable for clinical usage with high-accuracy
- Quick 1-second readings
- Auto shutoff to save battery power
5 Ways Being Pregnant With Fever Can Affect Your Baby
Being pregnant with a fever may affect your baby in numerous ways.
Neural Tube Defect Risk
Several studies show an association between having a fever during pregnancy and neural tube defects, like spina bifida.
But if you get a fever, there’s a way you can reduce the risk of neural tube defects: Take folic acid. A 2018 study found that although there was an association between fever and increased risk for neural tube defects, mothers who took folic acid didn’t have the same risk.
As you likely know, pregnant people should take 400 mcg of folic acid daily to prevent birth defects. If you’re taking your prenatal supplement, you’re likely already getting the folic acid needed for this buffering effect.
Congenital Heart Defect & Facial Deformities Risk with Early Pregnancy Fever
A 2017 study suggested that a first trimester early pregnancy fever can increase the baby’s risk of developing congenital heart defects and facial deformities, like cleft lip or cleft palate.
This study suggested that the adverse effects of fever are from the fever itself, not the underlying illness.
The senior author of the study said that there needs to be more awareness surrounding fevers and the risk of birth defects. He reminded pregnant women that Tylenol (acetaminophen and paracetamol) is well-studied and thought to be safe during pregnancy for reducing fever.
Pregnant fever may raise your baby’s risk for autism spectrum disorder (ASD), according to a 2017 study by Columbia University. The highest risk seemed to be in the third trimester, raising the odds of ASD by 40%. If the woman reported three or more fevers after the 12th week, her baby’s risk rose by over 300%.
This study exploring autism and fever was the largest done to date, following over 95,000 children over the course of 10 years. The results were inconclusive on whether drugs that lower fever could reduce the autism risk.
Another 2019 study looked at the connection between fevers, infection, and autism. If there’s a link between fevers and autism, is the autism risk caused by the infection or the fever itself? Researchers of that study concluded that the inflammatory response from severe infections may be a cause, rather than the fever itself. More research needs to be done to definitively say whether the infection or fever itself causes an increased risk.
A fever late in pregnancy can heighten your risk of preterm labor, according to Merk Manual. It’s not clear whether this risk is caused by the fever itself or the underlying virus, like the flu.
Interestingly, a fever close to delivery may put your baby more at risk for pediatric infections. According to a 2022 study, a fever close to delivery is linked to higher rates of long-term infectious diseases for the baby.
A Big Caveat…
As we outlined above, pregnant fever may be linked to defects and autism. But the research isn’t clear enough to state that as a fact. As researchers gather more data on how fever affects development, the results may or may not change.
One thing is for sure though: It’s important to treat your fever and monitor it, especially during pregnancy.
While the risks can cause you to freak out, try not to panic! Fever raises your risks, but your overall risk remains low. With your doctor’s advice and monitoring, you’ll likely continue to have a healthy pregnancy.
Summary: Being Pregnant with Fever Effects
Fever is just another part of being sick but the risk is more serious if you’re pregnant. Research shows that fever may be linked to neural tube defects, congenital heart defects, facial deformities, autism spectrum disorder, preterm labor, and pediatric infections. However, it’s important to realize that more research needs to be done to confirm whether these effects are caused by the fever or the illness that causes fever.
While researchers continue to collect data, the best thing you can do is to report your fever to your doctor. They can help you find the underlying cause and best course of treatment. You’ll also need to continuously monitor your temperature to ensure it returns to normal and doesn’t get worse.
Have You Heard Your Baby’s Heartbeat Yet?
With a handheld fetal doppler, you can hear your baby’s heartbeat from home while she’s still inside the womb! Simply use the probe and free ultrasound gel to detect your baby’s heartbeat. You’ll be able to see the fetal heart rate on screen and hear the beat through speakers. Thanks to BabyDoppler’s connecting app, you can save the recording and hear it forever as a keepsake.