Food poisoning during pregnancy

What is listeriosis and how can it affect pregnancy?

Listeriosis is a kind of food poisoning caused by Listeria bacteria. During pregnancy, you can pass the bacteria to your baby. This can cause problems, including:

• Miscarriage. This is when a baby dies in the womb before 20 weeks of pregnancy. 
• Stillbirth. This is when a baby dies in the womb after 20 weeks of pregnancy.
• Preterm labor and premature birth. These are labor and birth that happen too early, before 37 weeks of pregnancy. Babies born prematurely may have health problems and birth and later in life.
• Low birthweight. This is when a baby is born weighing less than 5 pounds, 8 ounces.
• Life-threatening infections in your baby, including bacteria in the blood (called bacteremia) and meningitis. Meningitis is an infection that causes swelling in the brain and spinal cord. Infected babies may have health problems after birth, including seizures, blindness and problems with the brain, heart and kidneys.

Listeria may be in the soil, water, on animals and in animal waste. The most common cause of listeriosis is eating food with Listeria in it. Foods that are most likely to have Listeria include:

• Unpasteurized milk and foods made with it. If milk is pasteurized, it’s been heated to kill germs. Look for the word “pasteurized” on the label.
• Soft cheeses, like feta, Brie, Camembert, Roquefort and Mexican-style cheeses, like queso fresco, queso blanco, Panela and Asadero
• Deli meat, hot dogs, juice from hot dogs and dry sausages that are chilled or at room temperature
• Unwashed fruits, vegetables or sprouts
• Cold salads from delis or salad bars
• Refrigerated patés or meat spreads (Canned meat spreads are safe.)
• Refrigerated smoked seafood, including nova-style, lox, kippered, smoked and jerky

How do you know if you have listeriosis?

Signs and symptoms of listeriosis usually start a few days after eating food contaminated by Listeria, but they may not happen for up to 2 months. They’re usually mild and flu-like. Your health care provider can test your blood to see if you have listeriosis.  

Call your provider right away if you have:

• Being confused or having trouble with balance
• Fever or chills
• Headache
• Muscle aches
• Nausea (feeling sick to your stomach) or diarrhea
• Seizures
• Stiff neck

What is salmonellosis and how can it affect pregnancy?

Salmonellosis is a kind of food poisoning caused by Salmonella bacteria. Salmonellosis can cause problems during pregnancy, including:

• Dehydration. This is when you don’t have enough water in your body. Signs and symptoms of dehydration include feeling dizzy or lightheaded, having a fast heartbeat, having dark-colored urine and having a dry mouth and lips.
• Bacteremia
• Meningitis
• Reactive arthritis (also called Reiter’s syndrome). This condition can cause swelling or pain in joints, like the knees, ankles and toes.

You can pass salmonellosis to your baby during pregnancy. If your baby is born with salmonellosis, she may have diarrhea and fever after birth. She also may develop meningitis.

You can get infected with Salmonella in two ways:

1. By touching an infected animal. Salmonella can be found in poop, soil, water (including fish tank water), food and bedding of infected animals, including pets. Salmonella germs can spread easily to an animal’s fur, feathers and scales. Animals that are most likely to carry Salmonella include reptiles (turtles, lizards, snakes) and poultry (chickens, ducks, geese).
2. By eating foods that are contaminated with Salmonella. These foods may look and smell normal, even if they’re contaminated.

Foods that often have Salmonella include:

• Raw or undercooked poultry, meat or fish. Cooking these items fully kills Salmonella.
• Raw or undercooked eggs and foods made with them. Salmonella can pass from chickens to their eggs. Even eggs that look normal can have Salmonella. Don’t eat food made with raw eggs, including homemade mayonnaise, hollandaise sauce, Caesar salad dressing, cookie dough, frostings and homemade ice cream.
• Unpasteurized milk, milk products and juice, or foods made from them. Milk and juice often are pasteurized. Look for the word “pasteurized” on the product label.
• Foods that come in contact with animal poop in the soil or water where they grow. These include mushrooms, fruits, vegetables and vegetable sprouts, like alfalfa, clover, radish and mung beans.
• Food that comes into contact with Salmonella while you’re making or serving it. For example, if you’re infected and don’t wash your hands after using the bathroom, you can spread the infection to food. Or if you use the same knife to cut raw chicken and tomatoes and don’t wash the knife in between, the knife can pass Salmonella from the chicken to the tomatoes.

How do you know if you have salmonellosis?

You may be at increased risk of getting salmonellosis if you:

• Have reduced stomach acid from using medicines for heartburn (called antacids), like Tums^®.
• Have recently used antibiotics. Antibiotics are medicines that kill infections caused by bacteria.
• Have a digestive condition called inflammatory bowel disease (also called IBD). Digestion is the process of how your body breaks down food after you eat.
• Have a weak immune system or an illness like HIV, sickle cell disease or malaria
• Travel to places that don’t have good sanitation systems. This means they don’t have toilets and clean water for cooking and washing.
• Have a pet bird or reptile
• Live and eat in group housing, like a dormitory

Signs of salmonellosis usually start a half day to 3 days after contact and last for 4 to 7 days. To test for salmonellosis, your health care provider takes a stool sample (a sample of your poop) and sends it to a lab for testing.

Call your provider right away if you have any signs or symptoms of salmonellosis, including:

• Belly pain
• Blood in your poop or dark or amber-colored urine (pee)
• Dehydration
• Fever or chills
• Headache
• Muscle pains
• Nausea, diarrhea or throwing up

How is food poisoning treated?

Treatment depends on how sick you are. You may not need any treatment, or your provider may treat you with antibiotics to help keep you and your baby safe. If you have food poisoning, drink lots of water to help you stay hydrated (have water in your body). If you’re severely dehydrated (don’t have enough water in your body), you may need to go to the hospital for treatment.

How can you protect yourself and your baby from food poisoning during pregnancy?

Here’s what you can do:

• Wash your hands right before handling food. Wash your hands well with soap and water after using the bathroom.
• Wash your hands well with soap and water after touching animals or their food, bedding, tanks or waste.
• Don’t eat foods that are likely to be contaminated with Listeria or Salmonella.
• Handle foods safely whenever you wash, prepare, cook and store them. Wash knives, cutting boards and dishes used to prepare raw meat, fish or poultry before using them for other foods.

More information

Centers for Disease Control and Prevention

Food and Drug Administration

Last reviewed: May, 2016