• Eating a wider variety of foods from all over the world.
• Eating more foods that have been prepared outside our homes.
• Aware of more than five times the number of foodborne pathogens than we were 50 years ago!

1. Pregnancy makes it hard for the mother's immune system to fight off harmful foodborne bacteria.
2. Harmful foodborne bacteria can cross the placenta and infect the baby.
3. The fetus doesn't have a developed enough immune system to fight off harmful foodborne bacteria.

• Serious health problems
• Premature delivery
• Miscarriage
• Death

1. Listeria: This pathogen can cause listeriosis. It can be found in:

• Refrigerated, ready-to-eat foods (dairy, meat, poultry, and seafood)
• Unpasteurized milk and milk products or foods made with unpasteurized milk
• Soil

• Listeria is one of the most common causes of miscarriage resulting from infection of the fetus.²
• Most Listeria infections occur during the third trimester of pregnancy.³ This is because the function of the mother's immune system is particularly reduced during this time.
• The serious effects of listeriosis in pregnancy are suffered by the fetus or newborns rather than the pregnant woman.⁴
• Listeria can be found in soft cheeses made with unpasteurized milk.
• Studies show that pregnant Hispanic women may have a higher incidence of listeriosis than pregnant non-Hispanic women. This is most likely because they make and eat homemade soft cheese and other traditional foods made from unpasteurized milk. ⁵
• Infected fetuses can suffer mental retardation, blindness, seizures, and paralysis.

2. Methylmercury: A metal that can be found in certain fish. Mercury falls from the air and can get into surface water. Bacteria in the water transforms mercury into methylmercury. Fish absorb methylmercury as they feed on aquatic organisms. Methylmercury can be harmful to unborn babies if certain fish high in methylmercury are eaten by pregnant women.

• Larger fish that have lived longer have the highest levels of methylmercury because they've had more time to accumulate it. These fish include: swordfish, tilefish, king mackerel, and shark. Pregnant women, women trying to conceive, nursing mothers, and young children should not eat these fish. It's okay to eat other cooked fish/seafood as long as a variety of other kinds are selected during pregnancy or while a woman is trying to become pregnant. She can eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish. Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week.
• Methylmercury can build up in the mother's blood stream and pass from her blood into that of her unborn child.
• Some fish and shellfish contain higher levels of mercury that may harm an unborn baby or young child's developing nervous system.
• Methylmercury is removed from the body naturally, but it may take over a year for the levels to drop to a safe level. This is why women who are trying to become pregnant should also avoid exposure to methylmercury.

3. Toxoplasma: This parasite can cause toxoplasmosis. It can be found in:

• Raw and undercooked meat
• Unwashed fruits and vegetables
• Water, dust, and soil
• Dirty cat-litter boxes and outdoor places where cat feces may be found.
• Toxoplasmosis is one of the least known foodborne illnesses among consumers.
• Infants born to mothers who became infected with Toxoplasma for the first time just before or during pregnancy are at risk for severe toxoplasmosis.⁶ Babies can suffer hearing loss, mental retardation, and blindness.
• Pregnant women can get toxoplasmosis from cats. T. gondii infects essentially all cats that spend any time outdoors. Cats get this parasite by eating small animals or raw meat that's infected. The parasite is then passed on through the cat's feces. It doesn't make the cat sick, so pregnant women may not know if their cats have the parasite.

1. Centers for Disease Control and Prevention.
2. Ibid.
3. Washington State University, Food Safety During Your Pregnancy Brochure, February 2002.
4. Centers for Disease Control and Prevention, Media Relations: Facts About Listeriosis, December 25, 1998.
5. Centers for Disease Control and Prevention, Futura Mama (Expecting Mother): A Model Program to Decrease Illness Associated with Unpasteurized Milk Products in Pregnant Hispanic/Latino Women, June 2, 2002.
6. Centers for Disease Control and Prevention, Division of Parasitic Diseases - Toxoplasmosis Fact Sheet.

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For information about food safety, call the FDA's Food Information Line at: 1-888-SAFE-FOOD.