Listeria - Advice for pregnant women

Listeria infection (listeriosis) is a rare infection caused by a bug called Listeria monocytogenes that can contaminate food. It's a concern during pregnancy because it can be passed to the baby, even if the mother has mild or no symptoms.

How you get listeriosis

Listeriosis usually occurs through eating food that has been contaminated with listeria. Foods that are not cooked or have been refrigerated for a long time can be sources of listeriosis.

Symptoms of listeriosis in pregnant women

Symptoms can be similar to the flu, including fever, tiredness, and muscle aches. Some women might also experience stomach aches or notice changes in their baby's movements.

What are the risks to the baby?

Listeria can be passed to the baby during pregnancy, potentially leading to miscarriage, stillbirth, premature birth, or serious illness in the newborn, such as meningitis.

How can I prevent Listeria infection during pregnancy?

Certain foods should be avoided during pregnancy, including:

• Any drinks or food made with raw (unpasteurised milk). This includes:
  • Raw unpasteurised milk and any drinks that use raw milk (such as smoothies)
  • Soft cheeses with white rind (e.g. Brie, Camembert, goat’s cheese)
  • Blue-veined cheeses (e.g. Stilton, Roquefort, Gorgonzola)
• Ready-to-eat cooked meats or meat products
• Cured or fermented meats or meat products eaten without further cooking e.g. parma ham, salami, chorizo, pepperoni
• Ready-to-heat meals
• Raw or smoked ready-to-eat fish, e.g. smoked salmon, smoked mackerel, marinated salmon, sushi, sashimi
• Ready-to-eat cooked crustacean meat e.g. crabmeat, lobster, prawn
• Live or cooked bivalve molluscs e.g. oysters, mussels, scallops, clams
• Ready prepared pre-packed chopped salads e.g. leaves, sprouted seeds, coleslaw
• Prepared salad items loose from salad bars/deli e.g. coleslaw, potato salad
• Pre-packed sandwiches
• Custom-made sandwiches from sandwich bars/deli
• Any paté (including vegetarian)
• Precut/prepared fruit, e.g. melon, fruit salad
• Frozen vegetables eaten without further cooking

Foods of most concern are those that do not require any further cooking or reheating such as chilled ready-to-eat foods.

For list of foods recommended to avoid during pregnancy go to https://www.safefood.net/Food-Safety/Food-poisoning/Listeria 

Food Safety

• Eat freshly cooked or prepared food
• Thoroughly wash fruits and vegetables before eating
• Cook all meat, poultry, and seafood thoroughly ensuring that it is served piping hot (food that requires cooking should reach 75°C for at least 30 seconds)
• Reheat leftovers until they are steaming/piping hot
• Be mindful of expiration dates on deli meats and other ready-to-eat foods and throw out any that has passed its use by date.

For advice on cooking and reheating food including leftovers go to https://www.fsai.ie/consumer-advice/food-safety-and-hygiene/cooking-and-reheating 

Food storage

• Keep your refrigerator between 0°C and 5°C
• Avoid letting food sit out at room temperature for more than two hours
• Always store raw meats separately from other foods

Hygiene

• Wash your hands frequently, and always before and after preparing food
• Use separate cutting boards and utensils for raw and cooked foods

On the farm

• Pregnant women should avoid helping ewes to lamb, cows to calve or goats to kid
• They should avoid contact with newly birthed animals, birthing products and contaminated material clothing, and equipment

Is Listeria passed on in breastmilk?

Listeria is not passed from a healthy mother to her baby in breastmilk. During pregnancy, listeria infection is passed from mother to baby through the blood stream or occasionally during birth. In general, even if a nursing mother is known to be infected with listeria, she should continue to breastfeed. If your baby was born very prematurely, or if you have other health concerns, your GP, obstetrician or midwife can advise you on the best way to feed and protect your baby.

What should I do if I think I have Listeria?

If you are pregnant and have any concerns about symptoms or suspect you've eaten contaminated food, you should contact your GP or healthcare provider. The symptoms of listeriosis in pregnancy are very non-specific, and any symptoms you have are very unlikely to be due to Listeria. However, if you are concerned you should let your doctor know. Early diagnosis of listeriosis in pregnancy and treatment with antibiotics can help reduce the risk of complications.

Last updated: 6 August 2025