Causes of Fever and Chills During Pregnancy

Fever or chills during pregnancy is a common experience; however, it's important to know that it's not an expected symptom of pregnancy. If you do encounter one of these things, it's possible you're dealing with an illness. These can range from mild to severe.

"It's easier to become sick when you're pregnant because your immune system is naturally suppressed," says Alyssa Dweck, MD, an OB-GYN in Mount Kisco, New York. However, there are some more serious conditions directly related to pregnancy that can cause these symptoms, too.

Ahead, you can find our comprehensive guide to understanding fever and chills during pregnancy. Here, you'll learn about the illnesses and conditions that may be to blame, as well as when to call a health care provider for assistance.

Common Causes of Fever and Chills During Pregnancy

If you're feeling feverish, have a case of chills, or are experiencing flu-like body aches during pregnancy, you may have one of these common bugs. But rest assured: They're all temporary and treatable!

Urinary tract infection (UTI)

Urinary tract infections (UTIs) are the most common bacterial infection among pregnant people. Approximately 8% of expectant people will get a UTI during their pregnancy.

Your urinary tract encompasses your urethra, bladder, ureters, and kidneys. An infection occurs when bacteria gets into this system and multiplies.

Most UTIs are bladder infections and aren't serious if they're treated with antibiotics and lots of liquids. If left untreated, however, a bladder infection may travel to the kidneys and cause a variety of complications, including preterm labor, a low birth weight baby, and sepsis.

Some UTIs are asymptomatic, but others come with symptoms such as a strong urge to urinate, a burning sensation with urination, cloudy urine, blood in the urine, fever and chills, and pelvic pain.

Influenza

If you’re experiencing fever or chills along with other symptoms such as flu-like body aches or coughing, you may have the flu. Pregnant people are at higher risk of getting the flu and becoming severely ill from it, as their immune systems are suppressed.

How can you tell if it's the flu or just a bad cold? The flu comes on quickly and the symptoms are more severe than with a cold.

If you suspect that you may have the flu, see your doctor right away. They'll likely recommend rest and plenty of fluids, along with an antiviral medication to shorten the span of your symptoms and prevent serious complications.

Common cold

We've all experienced this viral infection of the upper respiratory tract, which includes the sinuses, nasal passages, pharynx, and larynx. You may have symptoms that mirror the flu, as well as a runny nose, sore throat, cough, headache, and breathing difficulty.

Dr. Dweck notes that an upper respiratory infection is not as serious as the flu and usually resolves spontaneously. The symptoms usually last from three to 14 days, and you can treat them at home.

If you're still sick after several days, however, you may have a more serious infection (sinusitis, bronchitis, strep throat, or pneumonia), so it's important to see a health care provider.

Gastrointestinal (GI) virus

The diarrhea and vomiting brought on by a GI bug can have serious consequences for pregnant people if left untreated. Why? Because dehydration can cause contractions, preterm labor, and other potential side effects, like hypotension, dizziness, weakness, fainting, and, in severe cases, electrolyte imbalance.

Most cases of these viruses will resolve on their own, but fluids such as water or a sports drink like Gatorade along with the BRAT diet (bananas, rice, applesauce, and toast) can be helpful.

The Centers for Disease Control and Prevention (CDC) advises that you call your doctor immediately if you've not been able to keep liquids down for 24 hours, you've been vomiting blood, you have signs of dehydration (little or no urine, dry mouth, excessive thirst, dizziness), you notice blood in your bowel movements, or you have a fever above 101 degrees Fahrenheit.

Serious Causes of Fever and Chills During Pregnancy

In rare cases, fever, chills, and pain are linked to more serious medical conditions that affect pregnant people. Here are the symptoms to watch out for, as well as when to call a health care provider.

Chorioamnionitis

In addition to high fever and chills, this bacterial infection of the membranes surrounding the fetus (the chorion and amnion) and the amniotic fluid can cause sweating, rapid heartbeat, a tender uterus, and unusual vaginal discharge.

If a pregnant person has this infection they'll be put on antibiotics. After delivery, the baby will be checked for the infection and treated with antibiotics as well.

If chorioamnionitis is severe or left untreated, the expectant parent may experience infections of the pelvic region and abdomen, endometritis, and blood clots, and their baby could have complications including sepsis, meningitis, and respiratory problems. Risk factors for chorioamnionitis include prior amniocentesis (usually in the previous two weeks) and premature or prolonged rupture of the membranes.

Septic abortion

Septic abortion is when the uterus and its contents become infected as a result of a surgically or medically-treated miscarriage or abortion, explains Dr. Dweck. Symptoms include a high fever, chills, severe abdominal pain or cramping, vaginal bleeding and discharge, and backache.

Septic abortion is treated with antibiotics, and your health care provider will want to ensure that the uterus has been completely evacuated.

If the condition is left untreated, potentially fatal septic shock may occur. Signs of septic shock include low blood pressure, low body temperature, little urine output, and respiratory distress. Risk factors for septic abortion include poor surgical technique at the time of D&C and preexisting cervical/uterine infection.

Listeriosis

Listeriosis, or Listeria infection, is a bacterial infection that results from consuming contaminated food or water. Pregnant people, newborns, older adults, and adults with impaired immune systems are most at risk.

"Early symptoms of listeria [infection] may include fever, muscle aches, nausea, and diarrhea," says Dr. Dweck. "Symptoms may occur a few days or even two months after eating contaminated food." If the infection spreads to the nervous system, it can lead to headaches, stiff neck, confusion, loss of balance, or convulsions.

Not all babies whose gestational parents are infected will have a problem, but in some cases, untreated listeriosis can result in miscarriage, premature delivery, serious infection in your newborn, or stillbirth. Pregnant people can (and should) take antibiotics to treat the infection and help keep their baby safe.

Fifth disease (Parvovirus B19)

Fifth disease is a common childhood illness, so many adults are already immune to it. "The most common symptom in adults is joint pain and soreness that can last for days or weeks," says Dr. Dweck. "Symptoms of facial rash, slight fever, and sore throat are most common in children."

Although rare—less than 5% of all pregnant people become infected with parvovirus B19, according to the CDC—the virus can cause miscarriage and severe anemia in babies. Call your health care provider if you think you may have been in contact with a person infected with the virus.

Toxoplasmosis

Toxoplasmosis is a parasitic infection that can be contracted from cat feces or soil, or from eating raw or undercooked meat that contains the parasite. Sometimes it produces mild flu-like symptoms, or possibly no symptoms at all.

Because toxoplasmosis can be passed on to your baby, it can cause serious birth defects, especially in early pregnancy. Meanwhile, infection later in pregnancy can increase the risk of miscarriage and stillbirth, as well as cause babies to be born with brain damage.

Usually this condition can be diagnosed with a blood test. If your baby is not yet infected, you may be given an antibiotic, spiramycin (to help reduce the severity of symptoms in the newborn). But if your health care provider suspects that your baby is infected, you may be given two medications, pyrimethamine, and sulfadiazine. Infected babies also are treated at birth and through the first year of life with these medications.

Hepatitis B

This viral infection causes inflammation of the liver and creates flu-like symptoms like mild fever, headache, muscle aches, and tiredness. It also can cause loss of appetite, nausea, vomiting, and diarrhea, as well as dark-colored urine and pale bowel movements. Sometimes people also experience stomach pain, yellowing eyes and skin, and liver problems.

Hepatitis B can be passed on to your baby and have severe consequences for their health. It can also increase the risk of preterm labor. Typically, this condition is diagnosed with a blood test as part of a routine screening for all pregnant people. If they find you have hepatitis B, your baby will need a shot called HBIG, along with the first hepatitis B shot within 12 hours of birth.

Additional reporting by Tracee Cornforth.