Food poisoning while pregnant: symptoms, what to do and when to see a doctor

If you get food poisoning while pregnant, the first job is to keep fluids going: small, frequent sips of water, clear soup or oral rehydration salts such as Rehidrat or Dioralyte from the pharmacy. Most stomach upsets settle within one to two days. See a doctor if you have any fever, since HealthHub tells pregnant women to see a doctor for every fever, or if you can't keep liquids down, see blood in your stools, or have bad tummy pain. Go to hospital straight away if your baby is moving less than usual: KKH's Delivery Suite from 22 weeks, or its Urgent O&G Centre before that. Some infections are more dangerous when you're pregnant, and SFA says listeria is rare but can be fatal in pregnancy, and KKH's dietitians warn it can cause miscarriage and stillbirth.

Symptoms: is it food poisoning?

SingHealth's doctors say food poisoning usually starts 8 to 24 hours after you eat the contaminated food, with nausea, vomiting, diarrhoea and stomach cramps, and that a stomach bug usually clears within 24 hours to two days. The NHS notes that symptoms can sometimes start weeks after the meal, which is how listeria often behaves.

Because listeria can show up as a fever and aches without much vomiting, a flu-like illness after eating cold deli meat or soft cheese is worth a call to your doctor, even if your stomach feels fine.

What to do at home

SingHealth's Outram Community Hospital gives this advice for food poisoning and stomach flu, and it works in pregnancy too:

1. Sip clear fluids all day. Aim for about 8 to 10 glasses of water and non-oily clear soup. If your urine is pale and your tongue is wet, you're drinking enough.
2. Use oral rehydration salts if you're losing a lot of fluid. Rehidrat and Dioralyte replace the salts and minerals you lose. Boiled barley water or rice water with a pinch of salt also helps. Isotonic sports drinks are not the same as rehydration solutions.
3. Skip coffee, bubble tea and caffeinated packaged tea until you're better.
4. Eat plain food when you're ready: porridge, plain cream crackers, toast.
5. Rest, and keep a note of how often you're being sick or passing stools, to tell your doctor.

HealthHub's leaflet on oral rehydration salts asks you to tell your pharmacist you're pregnant before using them, so mention it at the counter. Don't take anti-diarrhoea pills without asking first. SingHealth says they shouldn't be used at all with a high fever or bloody stools, because these point to severe inflammation.

If someone at home has a stomach bug, SingHealth says to wash hands with soap and water, which kills norovirus better than hand sanitiser, and to leave bleach on soiled surfaces for at least 5 minutes before washing. The sick person should keep away from pregnant family members until they're better.

When to see a doctor

See a doctor the same day if you have any of these:

• A fever of any level. HealthHub tells pregnant women to see a doctor for every fever, and 37.5 degrees C or more counts.
• You can't keep liquids down, or you're showing signs of dehydration: dry lips, extreme thirst, peeing less, dark urine or dizziness.
• Blood or mucus in your stools or vomit, or black, sticky stools.
• Severe tummy pain.
• Diarrhoea that lasts more than 2 days even after you've treated it yourself.
• More than six watery stools in 24 hours.
• Flu-like aches after eating a listeria-risk food.

SingHealth notes that pregnant women count as a high-risk group, so with severe symptoms your doctor may prescribe antibiotics. KKH's obstetric advice adds fever as a reason to come straight in.

When to go to hospital now

• Your baby is moving less than usual
• You're dehydrated and still can't swallow liquids
• You have heavy bleeding or severe pain
• A severe headache with a stiff neck, or sudden confusion, which the NHS lists as signs of listeria spreading

In Singapore, KKH asks women 22 weeks or more pregnant to go to its Delivery Suite at Level 2 of the Women's Tower, and those under 22 weeks to its Urgent O&G Centre at Basement 1, open 24 hours. Otherwise go to your nearest emergency department.

Avoiding food poisoning in pregnancy

Our guide to foods to avoid during pregnancy lists each food and a safe swap. The habits that matter most, from SFA and KKH:

• Eat food hot and freshly cooked. KKH's dietitians say food should be served hot, not at room temperature, because bacteria multiply at room temperature.
• Don't eat cooked or ready-to-eat food that has been sitting between 5 and 60 degrees C for more than four hours. SFA's rule is to keep hot food above 60 degrees C and reheat leftovers until they're above 75 degrees C. That means steaming all the way through.
• Ask the stall to leave out the cockles, or to cook shellfish through. SFA says pregnant women should avoid raw or undercooked bivalves and can ask an eatery to cook a dish more.
• Heat cold cuts until steaming, and skip dry-cured raw ham and salami, as SFA advises.
• Choose pasteurised juice from the supermarket over fresh juice from a food court, and skip ready-to-eat salads, as KKH suggests.
• Use separate chopping boards for raw meat and for fruit or other food you won't cook.

At hawker centres, KKH's dietitian suggests choosing dishes cooked after you order, and being careful with pre-cooked food left out, such as Indian rojak, steamed chicken rice or nasi padang. Our guide to eating well in pregnancy covers what to eat more of, and coffee while pregnant has the caffeine limits for kopi and teh.

Frequently asked questions

What should I do if I get food poisoning while pregnant?

Sip clear fluids or oral rehydration salts, rest, and eat plain food when you can. See a doctor if you have any fever, can't keep liquids down, see blood in your stools or have severe pain, and go to hospital if your baby is moving less.

Can food poisoning harm my baby?

Most mild food poisoning doesn't, if you stay hydrated. Listeria is the main worry: it's rare, but SFA says it can be fatal in pregnancy and KKH says it can cause miscarriage or stillbirth. A high fever and dehydration also need treating promptly.

Can I take oral rehydration salts while pregnant?

Yes, they're used for dehydration from vomiting and diarrhoea. HealthHub's leaflet asks you to tell your pharmacist you're pregnant first.

How long does food poisoning last?

SingHealth says a stomach bug usually clears within 24 hours to two days, though listeria can take weeks to show. See a doctor if diarrhoea goes on for more than 2 days or you can't keep fluids down.

Should I see a doctor after eating a risky food?

Not if you feel well. The NHS says these foods don't always carry listeria and you don't need to do anything unless you get symptoms. Watch for fever, aches or a tummy upset over the next few weeks, and call your doctor if they appear.

Keep track of where you are with our due date calculator, and see common pregnancy discomforts by trimester for what's normal.