Pregnancy and food poisoning

Food poisoning is an unpleasant experience but most people recover without any ill effects. But there are particular risks for pregnant women. These range from dehydration caused by vomiting and/or diarrhoea through to birth defects and miscarriage.

The main risk is that of damage to the unborn baby caused by bacteria which are responsible for food poisoning. The worst case scenario is premature birth, stillbirth or miscarriage.

What causes food poisoning?

Bacteria, viruses or parasites cause food poisoning but there are a few which are particularly problematic for pregnant women. These include e coli, salmonella, campylobacter and listeria.

These can all spread to the unborn baby via the placenta where they will cause a range of health problems at birth which include meningitis. In some cases they may lead to a stillbirth.

But the worst is listeria. This is one type of bacteria which pregnant women need to be aware of as it is can cause both the mother and baby to become seriously ill. It is also responsible for a series of complications which can result in long term health problems in the baby. These can range from plain nasty through to fatal.

The effect of food poisoning on your pregnancy

If you are pregnant and you develop food poisoning then in most cases, it will not cause any long term problems for both you and your baby; however, you can expect it to be more unpleasant than usual due to the fact that your body is already under pressure as a result of your pregnancy.

So, look at reducing your risk of food poisoning as much as possible. That means taking notice of food safety and hygiene and being careful about the types of foods that you eat. Avoid those foods which are a known risk for listeria.

Basically, the healthier you are the better that is for your unborn baby.

The issue here is that the effects of food poisoning are more likely to cause problems for your unborn baby than for you. Your unborn baby is a greater risk due to it having an underdeveloped immune system which makes it vulnerable to all types of infections. This includes bacterial food poisoning.

Find out more in our preventing food poisoning section.

Listeria and pregnancy

Listeria food poisoning or listeriosis is caused by the consumption of foods which contain these bacteria. Examples of these include soft cheese such as Camembert or Brie; blue cheese; butter, pates; cooked meats such as ham or salami; and ready meals which are found in the chiller cabinet in supermarkets.

Unwashed fruit, vegetables and salads are also a factor as is unpasteurised milk. Undercooked meat and fish are also a danger.

If you are pregnant then you will have been advised to avoid these foods due to these risks. Choose hard cheeses such as Cheddar, pasteurised milk, yoghurts and cottage cheese. Make sure that you wash all salads, fruit and vegetables before you eat them.

Pregnant women are at greater risk of listeriosis which may be due to a lowering of their immunity plus changes to their metabolism. A weakened immune system is one of the risk factors for food poisoning and other illnesses as it is less able to fight the bacteria which cause these.

If you eat food which has been contaminated by the listeria bacteria then these will pass into your intestine via digestion. Once there they release toxins into the lining of the intestine which results in an infection.

This infection causes symptoms such as nausea, stomach pains, vomiting and diarrhoea.

Complications include blood poisoning (septicaemia), confusion, seizures and stillbirth or miscarriage in pregnant women.

Listeria and the unborn baby

If a pregnant women contracts listeriosis in the 14^th week or onwards of her pregnancy then this is likely to affect the health of the baby. This can only be detected via a blood test or an ultrasound scan.

Unfortunately, babies can become infected with listeriosis during birth if the bacteria are present within the mother’s vagina. These symptoms may not be apparent at birth but can develop later on. These can cause:

• Jaundice
• Pneumonia
• Meningitis

What also needs to be taken into account is that any infection, even if it is relatively mild, will deprive the unborn baby of essential nutrients which are vital for its development.

One example of this is toxoplasmosis which is spread via contact with infected cats (or their litter). If this spreads to the unborn baby then it is likely to cause birth defects or even a miscarriage.

This is why it is advisable for pregnant women to avoid any contact with cat litter or an infected animal during their pregnancy.

Treatment for food poisoning during pregnancy

If you are pregnant and suspect that you developed food poisoning then ask your midwife or GP for advice. Do this if you think your illness is caused by listeria bacteria as these can be dangerous during pregnancy.

Your GP is required by law to notify the authorities about any case of food poisoning.

You will need to rest during this time, drink plenty of fluids and take an oral re-hydration powder if necessary. This powder contains electrolytes which are vitamins, minerals and sugars, essential for the everyday functioning of the body.

These powders are available as sachets from your local chemist.

Your GP will perform a blood test and if this shows that you have bacterial food poisoning then you will be prescribed antibiotics to treat this. He or she will check that these are safe for you to take during your pregnancy.

Preventing food poisoning during pregnancy

There are a few steps you can take to reduce your risk of food poisoning. These include only eating foods which are safe to eat during pregnancy; washing your hands every time you handle food; checking that food is cooked properly and using food before its ‘use by’date.