Listeria (aka Listeriosis) is an infection caused by the bacterium Listeria monocytogenes. 

Why Do OB/GYNs Care About Listeria During Pregnancy?

Because pregnant women can pass the Listeria infection on to their developing babies.

PediaTrivia:

  • Pregnant women are 10 times more likely to be infected with the Listeria monocytogenes bacterium than the general population. Why? Because pregnancy weakens the immune system, making pregnant women more susceptible to bacterial infections such as Listeria. 
  • Hispanic women have an even higher risk of contracting Listeria when they’re pregnant. In fact, they’re 24 times more likely to get Listeria than the general population. This is due, in part, to the fact that many of the soft cheeses popular in Latin America (e.g Queso Blanco and Queso Fresco) are unpasteurized and can harbor Listeria monocytogenes.1

The Reason Listeria is a Sneaky SOB:

Listeria is sneaky because it only causes a mild flu-like illness in Moms-to-be (or no symptoms at all).  As a result, it often goes undetected in pregnant women. However, even if Mom-to-be has no symptoms of Listeria, she can unwittingly pass the infection onto her fetus.  Unfortunately, Listeria can have serious consequences for the developing baby (think: miscarriage, stillbirth, and preterm labor). 

The Good News: 

You can take several precautions to protect yourself against Listeria. 

For example, you know how everyone is always raining on your parade and telling you not to eat undercooked meats, soft cheeses, and hot dogs while pregnant? Well, what they’re really telling you is not to eat Listeria monocytogenes

Here are Some Specific Precautions That You Can Take to Minimize Your Exposure to Listeria monocytogenes During Pregnancy:

  • Say no to deli meats, hot dogs, and smoked fish.
  • Avoid raw sprouts (including alfalfa sprouts and mung beans).
  • Don’t eat or drink unpasteurized dairy products, including:

    • Soft cheeses made with milk that hasn’t been pasteurized (e.g. Brie, Camembert, blue cheese, queso blanco, and queso fresco).

    • Unpasteurized milk.

    • The homemade versions of eggnog, mayonnaise, and Caesar salad dressing.

    • Hollandaise sauce.
  • Wash all of your fruits and veggies before eating them and refrigerate your cantaloupe (who knew?!).
  • Cook meat thoroughly.

    PediaTip: Invest in a meat thermometer.
  • Wash your hands after handling uncooked meat and don’t forget to clean your cutting boards too.

The Bottom Line

Although Listeria can cause problems for fetuses, you and your developing baby should be in good shape if you avoid the foods above.