As if pregnancy isn't difficult enough, what with changing hormones, an expanding body, and all the other annoying, arguably weird symptoms, there's the potential for a fever. I mean, come on, pregnancy gods. Give it a rest. But, alas, during 40 weeks (more or less) a woman's suppressed immune system has to work extra hard to keep both mom and fetus healthy. So, how high of a fever can a pregnant woman have? After all, even the most run-of-the-mill cold can be scary when your body is doing something as difficult and incredible as growing a human being inside your own body.
Pregnant women are actually more likely to suffer from the flu, colds, and other viral infections because the immune system is suppressed during pregnancy. A fever is usually the result of an underlying cause, such as an infection or a virus, and it’s the result of your body honing in on whatever has attacked your body, and attempting to eradicate it. The temperature considered a fever in pregnant women is 100.4 degrees Fahrenheit, the same as it is for the general population, says Dr. Katherine Apostolakis-Kyrus, M.D., maternal-fetal medicine physician at Johns Hopkins All Children’s Hospital, in an interview with Romper. Given your suppressed immune system while you’re expecting, it’s possible you might find yourself feeling under the weather more than usual, and it’s not uncommon to be concerned for both you and your baby’s health.
Generally, a mild, low-grade fever or even a high fever of limited duration is not cause for serious concern if treated promptly, says Dr. Kenosha Gleaton, M.D., OB-GYN at Roper St. Francis Healthcare. The recommended course of action for pregnant women with a fever is to record their temperature and any other symptoms, take Tylenol, and call your OB-GYN for an assessment, she explains.
So what’s the risk of having a fever during pregnancy? Well, it varies from nothing more than discomfort, to much more at stake. Fevers in combination with a flu or cold, may be related to some birth defects, per the Centers of Disease Control and Prevention. One 2017 study published in Science Signaling suggests that if an expectant mother has a fever during the first three to eight weeks of pregnancy, it could interfere with baby's heart and jaw development. The result could be a baby born with a heart defect or facial abnormalities, like a cleft lip or palate.
Doctors agree that while there are various studies connecting prenatal fevers and birth defects, nothing is concrete. Dr. Gleaton emphasizes that there are “no consistent studies that demonstrate a cause-effect relationship between maternal fever and birth defects.” And Dr. Apostolakis-Kyrus agrees: “Fetuses are resilient and rarely have severe complications from a maternal fever. There is no known risk of congenital malformations from a fever.”
Given that a fever is a way for our body to tell us something’s not quite right, the most important thing to find out is what’s causing the fever, says Dr. Apostolakis-Kyrus. “Is it perhaps a reaction to a medication or a maternal infection that could potentially be transmitted to the fetus? If it is an infection, where is it?”
Other than the common bugs going around, Some other less common causes of a fever include urinary tract infection, the foodborne illness listeria, and an infection of the membranes surrounding the fetus, per Parents Magazine. “If the fever is from a maternal infection such as the flu, the most important thing will be to treat the mother to keep her healthy to continue her pregnancy with the least amount of complications,” says Dr. Apostolakis-Kyrus. However, she says, if the infection is in the amniotic sac, then the treatment calls for delivering the baby to avoid life-threatening complications.
So, how are you supposed to know when to call the doctor? The Bump recommends that a doctor should be called if you've held a fever for 24 to 36 hours, and especially if you have a rash, nausea, and/or vomiting (as previously mentioned). While Ibuprofen and other nonsteroidal anti-inflammatory drugs can harm the baby's cardiovascular development, acetaminophen is said to be a safe bet, along with a lukewarm bath and a cold compress or cloth on your head.
When it comes down to it, having a fever, however slight, during pregnancy isn't fun. Aside from rest and cold compresses, the best thing you can do is talk to your doctor sooner than later and let them know your symptoms to determine if you should be seen or be prescribed something to bring the temperature down. You never know if it's worth checking into or not, but with so much at stake, it can't hurt to call your healthcare provider and voice any questions or concerns you have, and your doctors will be able to take your medical history into account and let you know how much monitoring you need.
Katherine Apostolakis-Kyrus, M.D., maternal-fetal medicine physician at Johns Hopkins All Children’s Hospital
Kenosha Gleaton, M.D., OB-GYN at Roper St. Francis Healthcare
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