Expecting mothers are barraged with information about what to eat and what to avoid during pregnancy.  

Making sure you consume the appropriate nutrients for yourself and the baby growing inside you is important, but it’s not just about nutrients.  When you’re pregnant your immune system functions differently than when you’re not.  Expecting women need to know the risks associated with the foods they’re putting in their bodies.  

pregnant-belly.jpgAccording to the Centers for Disease Control and Prevention (CDC), one-third of all listeriosis cases in the U.S. occur in pregnant women.  Pregnant women are 20 times more likely than other healthy adults to get listeriosis, which can cause miscarriage or stillbirth.

Listeriosis is caused by the ingestion of Listeria monocytogenes (L. monocytogenes) bacteria.  While most bacteria grow poorly when temperatures fall below 40 degrees Fahrenheit, L. monocytogenes survives at temperatures from below freezing to body temperature, and grows best in the zero to 50 degrees Fahrenheit range, which includes the temperature range used for freezing and refrigeration.  

Foods pregnant women should stay away from include soft cheeses such as queso fresco, feta, brie, Camembert, blue cheese, and Roquefort as well as cheeses made from raw milk.  Hard cheeses, semi-soft cheeses such as mozzarella, and pasteurized processed cheeses such as cream cheese and cottage cheese are generally safe to eat.  

Other foods that should be avoided include refrigerated smoked seafood out of a package and refrigerated meat spreads and pates.  Canned seafood, meat spreads and pates are safe.  


Ready-to-eat foods like hot dogs, cold cuts, and lunch meat should only be eaten if they are reheated until steaming hot.  Meat and seafood should be cooked all the way through, and leftovers should be reheated until steaming hot.  Pregnant women should not consume store-bought sliced melon, and should wash all fruit and vegetables before eating them.  

If a pregnant woman becomes ill with listeriosis during he first trimester of pregnancy, listeriosis may cause miscarriage.  As a pregnancy progresses, a woman’s risk for listeriosis increases, and the infection can lead to premature labor, the delivery of a low-birth-weight infant, or infant death.  The U.S. Food and Drug Administration states on its Website:

Fetuses who suffer a late infection may develop a wide range of health problems, including mental retardation, paralysis, seizures, blindness, or impairments of the brain, heart, or kidney. In newborns, L. monocytogenes can cause blood infections and meningitis.

The CDC estimates that 2,500 people become ill with listeriosis every year.  Of those, 500 die.  
To learn more about listeriosis and pregnancy, visit the FDA website.