Food safety is always essential but it becomes even more vital when you have a bun in the oven. Blame your hormones for that extra hassle: it seems that the hormonal changes that occur during pregnancy lower the immune system. This can make it harder for you to fight off illnesses and infections and can put your baby and yourself at risk of severe food borne illnesses. This article highlights a few food borne illnesses and the best ways to prevent them.


Listeria monocytogenes is the infamous bacterium which causes listeriosis. Pregnant women have a 20 times higher risk of developing listeriosis compared to the general population. However, the bacterium does not usually constitute a serious threat for the mother. The real issue with Listeria is that it may not make you feel sick but it can affect your unborn baby whose immune system has not developed yet.

Listeriosis can cause miscarriage — about 22% of pregnancy-related cases of listeriosis result in the newborn’s death. Listeriosis can also cause your baby to be born prematurely — before the 37th week of gestation — or to be born with a low birth weight. In newborns, listeriosis can also lead to blood infections and meningitis.

The symptoms of a listeriosis infection include fever, headache, fatigue, muscle aches, nausea and vomiting. Severe symptoms include a stiff neck and severe headache.

The food culprits: Because Listeria can still thrive at 0.6C (33F), the major food sources of the bacteria include refrigerated and ready-to-eat foods:

  • Processed meats — Cold cured meats (like deli ham or turkey, parma ham, chorizo and salami).
  • Refrigerated pâtés or meat spreads — this includes foie gras.
  • Refrigerated smoked seafood unless it’s cooked prior to consumption.
  • Raw or undercooked animal meats — sushi, rare meat, eggs and oysters.
  • Unpasteurised milk

Current UK recommendations don’t advice against eating cold cured meats or smoked fish during pregnancy. Also, it is safe to eat sushi made with raw fish that has been previously frozen. Other high-risk foods, including pâtés, raw or undercooked animal meats, as well as raw or unpasteurised milk should be avoided.

You may also want to be picky about where you eat — according to the NHS about 1 in 20 people may carry the bacteria without presenting any symptoms of listeriosis. Hence, if contaminated food handlers do not wash their hands after going to the toilet, they may contaminate the food.

How to fight Listeria

  • Avoid keeping chilled foods at room temperature for more than 4 hours — after that, you should discard them.
  • Use opened foods within two days (provided you’ve kept that food in the fridge).
  • Eat foods by the ‘use-by’ date.

Make your refrigerator a Listeria-free zone

Because Listeria can grow in the refrigerator, storing a contaminated food in your fridge may cause the germ to multiply and spread to other foods as well. Here’s what you can do to prevent this:

  • Wrap or cover your foods with some foil paper or keep in air-tight containers.
  • Regularly check the temperature of your refrigerator: it should be set at 5oC or lower.
  • Clean your hands and kitchen surfaces often.


Have you heard about Salmonella? Well, that’s the bad bug that causes salmonellosis, a food borne illness that causes nausea, vomiting, headache, fever, abdominal cramps and diarrhoea. These symptoms usually appear within 12 to 72 hours after eating contaminated food and typically last for up to a week.

The food culprits: Raw eggs, products containing uncooked eggs (like mayonnaise) and unpasteurised eggs with a cracked shell.

How to fight Salmonella

  • Refrigerate your eggs: Keep them in their original container for up to 5 days after production. Discard refrigerated hard-boiled eggs after 7 days.
  • Thoroughly cook your eggs: Yes, that’s applicable to both the white and the yolk.Can’t stop thinking about poached eggs or sunny side-up? Unless you have pasteurised eggs on hand, make sure the yolk is set or go for a hard-boiled egg instead.
  • Don’t lick the cookie dough off that spatula.
  • Use an egg separator: It may be easier to use the egg shell to separate the white from the yolk but doing so may cause cross-contamination.

Campylobacter infection

Caused by Campylobacter Jejuni, this bad bug can make you sick 2 to 5 days after you’ve eaten a contaminated food. This pathogen causes diarrhoea, stomach cramps, fever, muscle pain, headache and nausea — these symptoms usually last for 7 to 10 days.

The food culprits: Raw milk and soft cheeses. Compared to hard cheeses, these are less acidic and thus contain more moisture; the perfect haven for dangerous pathogens.

How to fight Campylobacter Jejuni

  • Avoid mould-ripened soft cheeses like brie and camembert whether they’re produced from cows’ or goats’ milk.
  • Avoid soft-blue veined cheese like Danish blue, gorgonzola and Roquefort.
  • Other types of cheeses, such as feta, mozzarella, paneer, halloumi or ricotta should also be avoided if they are made from unpasteurised milk.

Caution: If you’re dining out, make sure to ask the chef whether the dish you’ve selected contains any cheese as this probably won’t be mentioned on the menu.


This food borne illness may occur after consumption of a food contaminated with Toxoplasma Gondii. A woman who becomes newly infected with Toxoplasma during or just before pregnancy can transmit the infection to the unborn baby. The earlier the infection occurs, the greater the risk that the baby will be severely affected. Toxoplasmosis may induce miscarriage, stillbirth or birth defects.

How to fight toxoplasmosis

  • Avoid direct contact with your cat’s faeces.
  • Cook your meat until well done.
  • Wash fruits and veggies thoroughly as soil can sometimes be contaminated with the bacterium.
  • Use gloves when handling soil.


Clostridium Botulinum is the bacterium that induces botulism and produces a toxin that causes muscle paralysis. Dry mouth and double vision may occur within 4 to 6 hours after ingesting contaminated food. This is followed by nausea, vomiting and diarrhoea. Constipation, weakness and breathing difficulties may also arise.

The food culprits: Home-canned and prepared foods.

You think you may be infected?

Don’t take any risks: if you experience any of the symptoms mentioned — even if they are mild — it’s imperative that you seek immediate medical attention.


    Food and Drug Administration. Food Safety for Moms-to-Be (Accessed July 2013).

    Food Standards Agency. Listeria - keeping food safe (Accessed July 2013)

    Lin CTJ, Morales A and Alston K (1997) Raw and undercooked eggs: A danger of Salmonellosis. Food Rev. 20:27–32.

    NHS Choices. Listeriosis (Accessed July 2013).

    Tam C, Erebara A and Einarson A (2010) Food-borne illnesses during pregnancy: Prevention and treatment. Can Fam Physician. 56(4): 341–43.