Articles

Key takeaways

• Your immune system changes during pregnancy, which can increase your risk of infection.
• Some infections can cause serious health problems for your baby.
• Simple food safety and hygiene steps can help prevent infections.
• Vaccinations and screenings protect both you and your baby.

Why preventing infections in pregnancy is important

During pregnancy, your immune system changes to support your growing baby. This means you can be more open to infections. Some infections can cause complications during pregnancy.

While most people have healthy pregnancies, some infections can be serious. In rare cases, they can lead to serious complications like stillbirth (when a baby dies after 24 weeks of pregnancy). Infections during pregnancy can also lead to health problems for you.

Simple steps can help you and your baby stay healthy and reduce the risk of infection.

Common infections to be aware of

Listeriosis

Listeriosis is an infection caused by listeria bacteria. It is normally caught by eating foods that have the listeria bacteria in it. These foods are often chilled, ready-to-eat items. Examples include:

• Unpasteurised milk and dairy products made from it.
• Mould-ripened soft cheeses (e.g., Camembert and Brie) and blue-veined cheeses
• Pâté
• Deli meats
• Pre-prepared sandwiches, salads and pre-cut fruit
• Smoked or cured fish (including in sushi)

Following food safety advice during pregnancy is the best way to avoid listeriosis. While it's rare, the infection can be serious in pregnancy. It could lead to miscarriage, stillbirth, or your baby being very unwell after birth.

Toxoplasmosis

Toxoplasmosis is an infection caused by a parasite called Toxoplasma gondii. This parasite mainly lives in cats. It can infect other animals and people.

If you get toxoplasmosis while pregnant, you can pass it to your baby through the placenta. This can increase your risk of miscarriage and stillbirth. It can also cause serious health problems for your baby. Toxoplasmosis can be caught by:

• Eating raw or undercooked meat, including meat showing any traces of pink or blood.
• Eating cured, dried, or smoked meats like salami.
• Eating raw oysters, clams, or mussels.
• Drinking unpasteurised goat's milk or products made from it.
• Contact with sheep or lambs.
• Eating unwashed fruit and vegetables contaminated by cat poo.
• Touching cat poo, for example, when changing a litter tray.
• Touching food after handling cat poo.

Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a common virus that most people have had and is usually harmless.

If you have an active CMV virus, you could pass it to your baby during pregnancy. This is called congenital CMV (cCMV). It can cause long-term health problems for your baby, which can include:

• Hearing loss
• Visual impairment or blindness
• Learning difficulties
• Epilepsy

You can get CMV from close contact with someone who has active CMV. CMV is found in a person’s:

• urine
• poo
• saliva
• blood

The risk of CMV harming your baby is highest if you get it for the first time in early pregnancy. This is during the first 12 weeks. After 12 weeks the risk becomes very low.

Group B Strep (GBS)

Group B Strep (GBS) is a common type of bacteria. It lives in the gut, vagina, and bottom (rectum) and is normally harmless.

If you have it when pregnant, there is a small risk it could spread to your baby during labour and make them ill. This happens in about 1 in 1,750 pregnancies. Most babies that come into contact with GBS are born healthy and remain well. However, in rare cases, GBS can cause serious illness in a baby when it is born. It has also been linked with an increased risk of miscarriage, stillbirth, and preterm birth.

If you are found to have GBS during your pregnancy, your healthcare team will discuss appropriate options for you during your birth.

Prevention through food safety and hygiene

You can pick up infections like listeria, salmonella, or toxoplasmosis from contaminated food. These can harm your baby if you catch them while pregnant.

Food safety to prevent listeria

• Pasteurised milk – Only drink milk that is pasteurised or UHT.
• Ripened soft cheese – Avoid eating varieties such as Camembert, Brie, or blue-veined cheese. Hard cheese varieties like Cheddar, cottage cheese, and processed cheese are safe.
• Pâté – Avoid eating.
• Undercooked food – Avoid eating. Make sure ready-prepared meals are cooked as per instructions and are piping hot when reheating.

Food safety to prevent salmonella

• Raw or partially cooked eggs – Avoid raw or partially cooked eggs not produced under the British Lion code, such as those in mayonnaise, soufflé, or mousse. These eggs are safe to eat once cooked until the white and yolk are hard.
• British Lion Code of Practice eggs – These are safe for you to eat raw or partially cooked. They have a red lion stamp on their shell.
• Raw or partially cooked meat – Avoid eating, especially poultry and shellfish.

Hygiene to prevent toxoplasmosis

• Hand washing – Always wash your hands before and after handling food.
• Fruit and vegetables – Wash all, including ready-prepared salads.
• Raw and chilled meats – Cook thoroughly.
• Gardening/soil handling – Wear gloves and wash your hands thoroughly afterwards.
• Cat poo – Avoid contact with (in cat litter or in soil). If you must handle it, wear rubber gloves and clean any trays daily.
• Sick cats – Avoid close contact with any sick cats.
• Gardening with no cat – Wear gloves, in case the soil is contaminated with cat poo.

General hygiene tips

• Hand washing – Wash your hands thoroughly with soap and water, especially after going to the toilet or changing nappies. Also wash hands before preparing food or eating.
• Unwell people – Try to avoid.
• Dirty cat litter/soil – Do not change or touch if it might be contaminated with cat poo.
• Cooked meals – Make sure all your meals are properly cooked, especially meat and shellfish.
• Reheating food – If safe to reheat, make sure it is steaming hot all the way through. Only reheat food once.
• Unpasteurised milk – Avoid milk and foods made with it.
• Sharing items with young children – Avoid sharing food, cutlery, or drinking glasses.
• CMV prevention with young children – Infections like CMV are common in young children. To help prevent catching CMV from them, try to avoid kissing them on the mouth and sharing a toothbrush.
• Farm animals – Avoid close contact with animals like pigs and sheep, as they can sometimes carry infections. If you work with livestock, speak to your midwife or GP for advice.
• Pork and pork products – Cook thoroughly.
• Touching animals – Wash your hands thoroughly afterwards. Always wash them before preparing, serving, and eating food.

The role of vaccinations and screenings

Recommended vaccinations during pregnancy are safe. They are recommended to protect both you and your baby.

Vaccines help your immune system recognise and create antibodies to fight common infections. The antibodies you produce pass through the placenta to your baby. This provides them with protection in their early months before they get their own vaccines.

The NHS recommends that you are vaccinated against flu (influenza) and whooping cough (pertussis). These vaccines are offered free on the NHS. Research shows these vaccines are safe for you and your baby. They help protect your health and your baby's health.

Flu vaccine

Pregnancy changes how your body deals with infections like flu. Catching flu during pregnancy can be more serious for you and your baby than at other times. Flu during pregnancy can sometimes make you so ill that you may require hospital treatment. It may also increase the risk of your baby being born prematurely. This is why the flu vaccine is recommended, as it's a safe and effective way to protect you both.

The vaccination also helps protect your baby in the first months of life. The flu vaccine is safe to have at any stage of pregnancy.

Whooping cough vaccine

Whooping cough can be a very serious infection. Young babies are most at risk. It can be especially serious for young babies, who often need hospital care to help them recover.

When you have the whooping cough vaccination in pregnancy, your body produces antibodies. These antibodies protect against whooping cough. They pass to your baby through the placenta. This gives them high levels of protection against serious whooping cough illness. This protection lasts until they can have their own whooping cough vaccination at 8 weeks old.

You usually have the whooping cough vaccine at 20 weeks pregnant. You can have it from 16 weeks.

To give your baby the best protection, you should have the vaccine before 32 weeks of pregnancy. If you miss having it before 32 weeks, you can still have it later.

Screenings

You will be offered a blood test for hepatitis B early in pregnancy. This is part of your antenatal care. Hepatitis B is a virus that infects the liver. If you have hepatitis B in pregnancy, you could pass the infection to your baby during pregnancy or birth. If you have the virus, your baby should be given the hepatitis vaccine at birth and at 4 weeks. They will also receive their routine vaccinations, which include the Hepatitis B vaccine.

In the UK, routine testing for Group B Strep (GBS) using vaginal and rectal swabs is not offered to everyone during pregnancy. This is because many people carry the GBS bacteria, and most babies are born healthy and do not develop GBS infection. Therefore, screening everyone in pregnancy isn't a reliable way to know which babies might get a GBS infection.

If however, you have already had a baby who had a group B strep infection, you will likely be offered antibiotics during labour. This reduces the chances of your new baby getting the infection. You will also likely be offered them during labour if you have had a group B strep urinary tract infection during the pregnancy.

When to contact your healthcare provider

Call your midwife, GP, or NHS 111 if you have concerns, or if you:

• Get a rash in pregnancy.
• Have symptoms you are worried about.
• Have been in contact with someone with an infection.

Some infections, like CMV, can cause mild illness with flu-like symptoms which include:

• Fever
• Sore throat
• Aching muscles
• Skin rash
• Feeling sick
• Tiredness (fatigue)
• Swollen glands

Call your GP or midwife if you are pregnant and have any of these symptoms.

Contact your midwife, GP, or NHS 111 as soon as possible if you have symptoms of toxoplasmosis, which include:

• A high temperature
• Aching muscles
• Tiredness
• Feeling sick
• A sore throat