Tommy's PregnancyHub

Infections in pregnancy

Getting an infection in pregnancy is not likely to harm your baby. But it is important to do what you can to avoid them.

Infections are caused by either bacteria or viruses. Bacterial infections, such as whooping cough, are usually treated with antibiotics. Viral infections, such as the common cold or chickenpox, can’t be treated with antibiotics, but there are ways to manage symptoms.

How to avoid infections in pregnancy

There are some simple steps you can take to avoid getting an infection in pregnancy:

  • wash your hands regularly with soap and water
  • try to avoid people who are unwell
  • have all the vaccinations you are offered in pregnancy
  • don’t change or touch dirty cat litter or contaminated soil
  • make sure all your meals are properly cooked, especially meat
  • avoid unpasteurised milk and foods made with it
  • avoid travelling to areas where you could catch the Zika virus until after your pregnancy
  • talk to your GP, doctor or midwife if you think you are at high risk of infection
  • get tested for sexually transmitted infections
  • avoid sharing food, cutlery, drinking glasses or dummies with young children
  • contact your GP, doctor or midwife if you have been in contact with someone with an infection, even if you don’t have any symptoms
  • contact your GP, doctor or midwife straight away if you have any symptoms of an infection.

Here’s more information about infections in pregnancy: 

Hepatitis B
Hepatitis C
Sexually transmitted infections
Slapped cheek syndrome
Whooping cough
Zika virus


Chickenpox is an infection that causes a rash and itchy spots. It is very infectious and you can catch it by being in the same room as someone who has it. If you’ve had chicken pox before, you can’t catch it again. Most pregnant women are immune to chickenpox infection, so it is rare to get chickenpox when you’re pregnant.

Chickenpox during pregnancy can cause complications. These can vary, depending on how many weeks pregnant you are. Most pregnant women who do get chickenpox recover, with no harmful effects on the baby.

Before 28 weeks of pregnancy

There is a small risk your baby could develop foetal varicella syndrome (FVS). This can damage the baby’s skin, eyes, legs, arms, brain, bladder and bowel. There is no evidence that catching chickenpox at this stage of your pregnancy increases the risk of miscarriage.

Between 28 and 36 weeks of pregnancy

The virus stays in the baby’s body but doesn’t cause any symptoms. But it may become active in the first few years of the baby’s life, causing shingles.

After 36 weeks

Your baby may be infected and could be born with chickenpox.

Symptoms of chickenpox include:

  • red spots that appear anywhere on the body
  • a high temperature above 38C
  • aches and pains, and generally feeling unwell
  • loss of appetite.

If you’ve never had chickenpox and you come into contact with someone who does, speak to your GP, doctor or midwife straightaway. They can do a blood test to find out if you are immune. If you’re not immune you’ll be given medication to manage the symptoms.


Cytomegalovirus (CMV) is a common virus that is usually harmless. Sometimes it can cause problems in babies if you catch it during pregnancy. This is known as congenital CMV infection. Complications may include hearing loss, visual impairment or blindness, learning difficulties and epilepsy.

There is no treatment for CMV in pregnancy, but there are things you can do to prevent it. In most cases the virus doesn’t cause any problems for your baby.

Find more about cytomegalovirus

Hepatitis B

Hepatitis B is a virus that infects the liver. Many people won’t have any symptoms, but can carry the virus and infect others. You can catch the virus by having sex with an infected person without a condom or by direct contact with infected blood.If you have hepatitis B in pregnancy the infection could be past on to your baby. 

All pregnant women are offered a blood test for hepatitis B as part of their antenatal care. If you have the virus your baby should be given the hepatitis vaccine at birth and further doses until they are 1. This is very effective in preventing babies developing long-term hepatitis B infection.There is a vaccine for pregnant women who may have a higher risk of getting hepatitis B.

This includes women who:

  • work in areas that puts them at risk of contact with blood or body fluids, such as nurses, prison staff, doctors, dentists and laboratories
  • may have travelled to high-risk countries such as sub-Saharan Africa, east and southeast Asia, the Pacific Islands, parts of South America, southern parts of eastern and central Europe, the Middle East and the Indian subcontinent
  • have a sexual partner with hepatitis B.

There’s no evidence of any risk to you or the baby from having the hepatitis vaccine. Talk to your GP, doctor or midwife if you have any concerns about hepatitis B.

Hepatitis C

The hepatitis C virus infects the liver, which is transmitted by direct contact with infected blood. Most people with hepatitis C have no symptoms and don’t know they are infected.You can catch the virus by having sex with an infected person without a condom or by direct contact with infected blood.

If you have the virus you may pass the infection to your baby. Doctors can’t stop this from happening, but the risk is much lower than with hepatitis B.Your baby can be tested for hepatitis C and if they are infected they will be referred for an assessment with a specialist. Talk to your GP, doctor or midwife if you are worried about hepatitis C.


Listeriosis is a rare infection caused by bacteria called listeria. The infection is rare, but even a mild case can cause serious problems if you’re pregnant. These include:

Listeriosis is usually caught from eating and drinking things that may contain listeria bacteria. These include:

  • unpasteurised milk
  • dairy products made from unpasteurised milk
  • soft cheeses, like camembert and brie
  • chilled ready-to-eat-food, like pậté and deli meats
  • foods past its use-by-date, even if it looks and smells normal.

You can also catch listeriosis from:

  • someone else who has it. For example, if you eat food they’ve touched when they haven’t washed their hands
  • close contact with farm animals, especially sheep and cows that are giving birth.

There are things you can do to prevent listeriosis, including:

  • wash your hands regularly with soap and water
  • wash fruit and vegetables before eating them
  • store ready-to-eat foods as recommended by the manufacturer
  • make sure all hot food is steaming hot all the way through.

Contact your midwife straight away If you’re pregnant and showing signs of listeria infection. These include:

  • a high temperature of 38C or above
  • aches and pains
  • chills
  • feeling sick or vomiting
  • diarrhoea.

You may need a blood test to check for the infection. If you have listeriosis you’ll be given antibiotics that can help prevent the infection harming the baby.

Smoked fish and listeria

Due to a listeria outbreak linked to smoked fish, people at higher risk of serious infection (including pregnant people) should only eat smoked fish products that have been thoroughly cooked. When cooking smoked fish products at home, make sure they are steaming hot all the way through.

Smoked fish includes salmon, mackerel, whitefish and trout. 

Find out more from the Food Standards Agency.

Rubella (also known as German Measles) in pregnancy

Rubella is a disease caused by a virus, which spreads in coughs and sneezes. It is very rare in pregnancy, but if you do get it while you’re pregnant it could harm your baby.Rubella can cause:

  • miscarriage
  • problems after the baby is born, such as brain damage, heart defects, deafness or eye problems.

These risks only apply if you get rubella early in pregnancy (before 16 weeks). There is no known risk to your baby after 20 weeks of pregnancy.

You are usually protected against Rubella if you had one rubella or two MMR vaccinations as a child or if you’ve had Rubella before. MMR stands for Measles, Mumps, Rubella. You can check with your GP if you’re not sure if you’ve been vaccinated. You may think you are immune to Rubella because you’ve had Rubella before, but you are only immune if a blood test says you are.

Speak to your GP about getting checked.If you need the MMR vaccine (jab), you should get it before you start trying for a baby. Women are advised not have the MMR vaccine during pregnancy because it uses the live version of the virus. This means there is a potential risk that the vaccine could infect the baby. Try not to worry if you were vaccinated shortly before you got pregnant or if you didn’t realise you were pregnant. This advice is given as a precaution and there have been no reported cases of the vaccine affecting a baby.

Contact your GP or midwife as soon as possible if you're pregnant and come into contact with anyone with rubella, or if you have any symptoms. These include:

  • a red or pink spotty rash
  • aching fingers, wrists or knees
  • a high temperature of 38c or above
  • coughs, sneezing and a runny nose
  • headaches
  • sore throat
  • sore, red eyes.

Sexually transmitted infections

Sexually transmitted infections (STIs) are passed from one person to another through sex or genital contact. They are sometimes known as sexually transmitted diseases (STDs).If they are not treated, some STIs can:

  • cause infertility 
  • cause health problems for you and your baby during (and after) pregnancy
  • be passed on to your baby.

Most STIs have no symptoms or only mild symptoms. So, many people who have an STI will not know they are infected and can pass it on to any sexual partners.If you have a new partner, you have symptoms or you are worried about STIs it is important to get tested. The best places to go are a genito-urinary medicine (GUM) clinic, sexual health clinic, your GP or a young people’s clinic.

All information given will be kept confidential, and the tests are only done with your permission.You can find details of local GUM clinics by contacting the Sexual Health Line on 0300 123 7123 or the Family Planning Association. The father should have a sexual health check-up too if you have concerns.


Shingles is an infection caused by the chickenpox virus. It can cause pain or tingling on the skin and a rash. This usually appears on the chest and tummy, but can also appear on the face, eyes and genitals.You can only get shingles if you have already had chickenpox. After you recover from chickenpox, the virus stays in your body and can become active again later in the form of shingles. You can't catch shingles from someone else.

If you haven’t had chickenpox before, it’s best to stay away from anyone with shingles. It’s possible to catch the virus that causes chickenpox from someone who has shingles, although the risk is low.

If you get shingles when you’re pregnant it’s usually mind and there’s no risk to you or your baby. But you should contact your midwife or GP because you may need treatment. 

Slapped cheek syndrome

Slapped cheek syndrome is caused by a virus called parvovirus B19. Many adults (60%) are immune to it. Most pregnant women who get slapped cheek syndrome have healthy babies. But getting slapped cheek syndrome during can increase the risk of miscarriage, especially in early pregnancy. But this risk is small and most women will already be immune (protected against infection).

If you get it between weeks 9 to 20, there’s also a small risk that the baby will develop foetal hydrops. This is a serious condition that can cause heart failure, anaemia and sometimes death.

Slapped cheek syndrome during pregnancy has not been shown to cause birth defects or development problems later in childhood.

Symptoms may include:

  • a high temperature  of 38C or more
  • a runny nose or sore throat
  • headache
  • after 1 to 3 days, a bright red rash may appear on both cheeks but adults don’t always get the rash.

See your GP or midwife as soon as possible if you’re pregnant and think you have come into contact with someone with slapped cheek syndrome. You should do this whether you get a rash or not.Your healthcare professional will do a blood test to check whether you have it. If you have the virus in the first 20 weeks of pregnancy, you’ll be offered ultrasound scans throughout your pregnancy to monitor your baby.


Toxoplasmosis is an infection that you can catch from the poo of infected cats, infected meat or contact with lambs or sheep. You can also catch it from soil that has had infected cat poo in it.

If you get toxoplasmosis for the first time while you're pregnant, or a few weeks before you get pregnant, there is a small risk that infection could cause:

  • miscarriage
  • stillbirth
  • congenital toxoplasmosis (where the infection spreads to your baby). This may cause birth defects or problems after they’re born.

If you are infected in early pregnancy it is less likely to spread to your baby, but if it does it can cause more serious problems. If you are infected later in pregnancy it is more likely to spread to your baby but any problems may be less severe.The chances of getting toxoplasmosis for the first time in pregnancy are small and in many cases the infection doesn’t spread to the baby. There are things you can do to prevent toxoplasmosis and treatment is available.

Find out more about toxoplasmosis.

Whooping cough

Whooping cough is a serious infection that causes coughing and chocking, making it hard to breath. Babies that are too young to be vaccinated are at risk of getting whooping cough and this can be very serious. Most will have to be hospitalised and some may die.

Getting vaccinated while you’re pregnant will help protect your baby from developing whooping cough in the first few weeks of their life. The immunity you get from the vaccine passes through the placenta to your unborn baby. This will protect them until they are vaccinated at 2 months old.

Zika virus

Zika virus disease is mainly spread by mosquitoes. It can also be transmitted through sex, although the risk is very low. Outbreaks have been reported in the Pacific Islands, South and Central America, the Caribbean, Africa and parts of south and southeast Asia. The risk of getting Zika in the UK is extremely low.The Zika virus is usually a mild infection, but it can cause birth defects in unborn babies including:

  • an abnormally small head (microcephaly)
  • abnormal brain development.

You can try to avoid getting the Zika virus by:

  • avoiding travelling to areas at risk of Zika virus transmission until after your pregnancy. Visit Gov.UK for up to date advice
  • talk to your GP, midwife or doctor if you must travel. They may be able to give you more advice
  • if you are in a high-risk area now, make sure you use condoms during sex while you are travelling and throughout your pregnancy.

See your GP, doctor or midwife if you are pregnant and have been in an area with a risk of Zika virus transmission. They can discuss the risks with you and organise some tests if needed.Contact your GP or midwife straight away if you have any symptoms. These include:

  • rash
  • itching all over the body
  • fever
  • headache
  • joint pain (with possible swelling, mainly in the joints of the hands and feet)
  • muscle pain
  • conjunctivitis (red eyes)
  • lower back pain
  • pain behind the eyes.

NHS Choices. Infections in pregnancy that may affect your baby (Page last reviewed: 08/02/2018 Next review due: 08/02/2021)  

Royal College of Obstetricians & Gynaecologists Chicken pox and pregnancy June 2015

NHS Choices. What are the risks of chickenpox during pregnancy? (Page last reviewed: 15/10/2018 Next review due: 15/10/2018) 

NHS Choices. Chickenpox (Page last reviewed: 26/05/2017 Next review due: 26/05/2020) 

NHS Choices. Cytomegalovirus (Page last reviewed: 01/09/2017 Next review due: 09/01/2020) 

NHS Choices. Hepatitis B vaccine (Page last reviewed: 08/02/2018 Next review due: 08/ 02/2021)

NHS Choices. Foods to avoid in pregnancy (Page last reviewed: 23/01/2017 Next review due: 23/01/2020) 

NHS Choices. Listeriosis (Page last reviewed: 13/10/2017 Next review due: 13/10/2020)  

NHS Choices. Rubella (Page last reviewed: 18/09/2018. Next review due: 18/09/2021)

NHS and Public Health England Thinking of getting pregnant? Make sure you’re protected against German measles MMR (measles, mumps, rubella) vaccine: advice for pregnant women. 25 June 2018

NHS Choices. Sexually transmitted Infections (Page last reviewed: 09/04/2018 Next review due: 09/04/2018) 

NHS Choices. What are the risks of shingles during pregnancy?  (Page last reviewed: 08/10/2018 Next review due: 08/10/21)  

NHS Choices. What are the risks of toxoplasmosis during pregnancy? (Page last reviewed: 28/04/2016 Next review due: 31/12/2018)  

NHS Choices. Whooping cough vaccination in pregnancy (Page last reviewed: 22/09/2016 Next review due: 22/09/2019) 

NHS Choices. Zika Virus (Page last reviewed: 10/12/2018 Next review due: 10/12/2021)  

Review dates
Reviewed: 31 January 2019
Next review: 31 January 2022

This content is currently being reviewed by our team. Updated information will be coming soon.