Intrauterine Infection: New Spins on an Old Problem

Note: The Pregistry website includes expert reports on more than 2000 medications, 300 diseases, and 150 common exposures during pregnancy and lactation. For the topic Intrauterine Infection, go here. These expert reports are free of charge and can be saved and shared.


As long as there have been pregnancies, there have been germs. (Actually, come to think of it, the germs came first.) Many, many different types of germs can cause infections in pregnant woman and harm both Mom- and child-to-be. And new ones are constantly being discovered.

As much as medical science strives to keep up with newly uncovered sources of infection, the ones we’ve known about for a while are still there. The good news is that the ability to diagnose and treat those infections is getting better and better. And there’s always more to say on the latest advances that have been made in taking care of women, fetuses and newborns who are at risk. Let’s look at what researchers are saying these days about a common infection known as chorioamnionitis.

The Name Game

Chorioamnionitis refers to a bacterial infection of the sac within the uterus that contains the developing baby and placenta (which feeds the baby).  Although this term has been around for generations, you might start hearing it under a new name: “intrauterine infection, inflammation, or both.”

No question, that new moniker is a mouthful. However, many researchers feel that it better describes what happens when a pregnant Mom is infected:

  • Bacteria make their way up to the uterus from other parts of the body (commonly the vagina or anus, where all sorts of bacteria live) and cause infection in the area.
  • In defense, the body makes all sorts of cells and chemicals in a process known as the immune response. While this might seem like a good thing—after all, the goal is to get rid of the offending bacteria—it can also cause problems and make both Mom and baby sicker. For example, one of the inflammatory chemicals can cause the uterus to contract early, leading to premature birth.

OK then, How About Some Good News?

Since bacterial intrauterine infection can be serious—in severe cases, a newborn can die from it—it seems a little strange to talk about anything “good” in this process. Yet, there are some good things that help us take care of the problem before it’s too late.

First off, any inflammation usually gives us clues that something’s going on. For example, we’ve all had fevers with infections, even minor ones. That’s an inflammatory response, and one we might see if intrauterine infection is present. Mom’s pulse might be high; that’s another sign. And any signs of labor well in advance of her due date will start providers looking for a germ that might be causing the problem.

As far as infection goes, the good news is that prompt testing is available for bacteria. The most common cause of intrauterine infection is a bacteria known as group B streptococcus (GBS), something that obstetricians have been testing pregnant women for in recent years. GBS doesn’t always cause problems, but because it can do so, providers watch pregnant women with the germ (as well as their newborns) more closely.

Babies at Risk for Infection: Watch or Treat?

Bacterial infections, especially the ones that cause uterine infection, are usually treatable with antibiotics if they are found. For that reason, Moms and babies have been commonly started on antibiotics if chorioamnionitis is suspected. But because antibiotics have their own risks, and because emerging antibiotic resistance means we might not have working medicines in the future, researchers are looking at different ways of telling whether there is an infection.

One hospital, in particular, has tried a new approach in babies whose mothers had chorioamnionitis. Newborns who looked healthy but would have received antibiotics in the past due to Mom’s infection were instead watched very closely by doctors and nurses in the hospital. They were able to avoid antibiotics in the great majority of babies without them getting sick. Those who did fall ill were able to receive the medicine in good time, due to the close observation.

Lessons for the Future

There is probably no one way of taking care of pregnant women and babies that is going to be the best way in all cases. Every situation is unique, and although providers do use guidelines, these change over time. By and large, this is as it should be, because several changing factors influence the risks of even an “old” infection like chorioamnionitis. Discuss these risks with your provider and your newborn’s provider. Realize that in many cases antibiotics may still be needed. And if your baby needs to stay in the hospital—whether for antibiotics or for simple observation—know that there can be very good reasons behind that recommendation!

Stan Sack
Dr. Stan Sack has 29 years’ experience as a primary care pediatrician in Massachusetts and Florida. A medical writer since 2015, he enjoys blogging on topics that are on parents’ minds but are covered less often in books and on websites. He lives in the Florida Keys with his family and enjoys healthy cooking, fitness activities and singing in his spare time.

Leave a Reply