Toxoplasmosis in pregnancy

Toxoplasmosis is an infection that can cause some complications if you catch it for the first time during your pregnancy.

What is toxoplasmosis?

Toxoplasmosis is a disease caused by a microbe called Toxoplasma gondii. Microbes are tiny living things that are found all around us. Some microbes are important for our health, but others can make us sick. 

Although often used interchangeably, ‘toxoplasma’ and ‘toxoplasmosis’ are not the same thing. Toxoplasma is the name of the microbe, and toxoplasmosis is the symptomatic disease that it can cause.

Why is toxoplasma dangerous in pregnancy?

If you become infected before you get pregnant, there will be a period of days to weeks where the microbe is active in your body and your immune system will have time to react against it. Once you have become immune, you be immune for the rest of your life. This means that if you had the infection before you got pregnant, your baby will be protected.  

But if you get toxoplasma for the first time while you're pregnant, or just before you get pregnant, you won’t have time to become fully immune. This means that there's a risk that the infection could cause complications to the pregnancy, and health problems in the baby after birth. 

How common is toxoplasmosis during pregnancy?

The chances of getting toxoplasma infection for the first time during pregnancy are thought to be very small. Over a five-year period (2008-2012), there were only 190 recorded cases of pregnant women diagnosed with the infection in the UK (although there may have been more). 

Even if you do become infected for the first time during pregnancy, this doesn't mean your baby will definitely get it. In many cases, the infection doesn't spread to the baby. It's estimated that only 1 in 10,000 babies is born with toxoplasmosis in the UK. 

How can you catch toxoplasmosis?

Most cases of toxoplasmosis are from eating contaminated food. You can be infected by:

  • eating raw or undercooked meat (meat showing any traces of pink or blood)
  • eating cured meats like salami or Parma ham (this is ok if cooked)
  • drinking unpasteurised goats’ milk or eating any products made from it
  • handling pregnant sheep or lambs 
  • eating food with cat poo or contaminated soil on it
  • touching contaminated cat poo (for example, by changing the litter box) and then touching food.

Stroking a cat or having a cat as a pet puts you at no greater risk of catching toxoplasmosis. 

You can’t catch toxoplasmosis through person-to-person contact. But mothers can pass the infection to their unborn baby through the placenta.

How is toxoplasmosis diagnosed?

Women are not routinely offered a test for toxoplasmosis as part of their antenatal care. But if you are worried, you can ask your midwife or GP for a blood test to check for the infection at any time during pregnancy.

If you have had a very recent infection, you’ll have more tests to check if there is any risk your baby is affected. Try to remember that this is very rare. 

What are the symptoms of toxoplasmosis?

It doesn't usually cause any symptoms and most people don't realise they have had it.

But some people get flu-like symptoms, such as:

  • high temperature (fever) 
  • aching muscles
  • tiredness
  • feeling sick
  • sore throat
  • swollen glands. 

If you have these symptoms, it doesn’t mean you definitely have toxoplasmosis. But you should always tell your doctor or midwife about any symptoms that you are concerned about in pregnancy

Who is at risk of toxoplasmosis?

Anyone who eats anything infected with the microbe is at risk. Pregnant women who work on the land, in catering or farming may be at higher risk as they may be more likely to come into contact with the microbe toxoplasma gondii. Lambing is a particular risk for pregnant women.

You are also more at risk also if you have a weak immune system, for example following organ transplant, cancer treatment, or if you have HIV. 

How do I reduce the risk of catching toxoplasmosis?

To reduce your risk of catching toxoplasmosis:

  • cover any children’s sandpits to prevent cats using them as litter boxes
  • wash your hands before preparing and eating food
  • wash hands, knives and chopping boards thoroughly after preparing raw meat
  • peel or wash fruit and vegetables thoroughly to get rid of any traces of soil
  • do not eat raw or cured meats like salami or Parma ham
  • do not have unpasteurised goats' milk or any eat products made from it
  • cook all meat thoroughly (leave no trace of blood or pinkness)   
  • wear gloves while doing any gardening and wash your hands and gloves afterwards
  • avoid eating while doing the gardening and avoid any areas where there may be cat poo
  • avoid gardening in areas that may have been soiled with cat faeces.

Find out more about foods to avoid in pregnancy and tips for food safety.

If you live in a farming environment, try to:

  • avoid contact with any animals (sheep, cows or goats) that are giving birth
  • avoid contact with newborn animals or their bedding
  • avoid handling and washing any clothes, boots etc that have touched animals that have given birth, or their young
  • make sure anyone else in the house wears protective clothing when any animals are giving birth and that these clothes are washed thoroughly in hot water afterwards.

Can I change the cat litter tray while pregnant?

Remember that you can’t catch toxoplasmosis by stroking a cat or having a cat as a pet. 

But if you have a cat, it’s best to take some precautions.

  • Ask someone else in the house to empty the cat litter trays if possible. If no one else can do it, wear disposable gloves while you do it and wash your hands thoroughly afterwards.
  • Change your cat litter tray every day and thoroughly clean it with hot water. This is because the microbe usually takes 2 to 3 days to become active after it is shed into the cat poo.
  • Wash your hands thoroughly if you accidently touch cat poo. 
  • Wash your hands thoroughly after handling cats and avoid close contact with any sick cats. 

What are the tests for toxoplasmosis in pregnancy?

It is diagnosed using a blood test, which can be done at any stage before or during pregnancy and will not harm your baby. 

This blood test looks for antibodies – the body’s natural defences – to the infection. It may take up to 3 weeks for these antibodies to be present following an infection. This means that it’s important to wait for 3 weeks before having the blood test to make sure the result is accurate. 

Depending on the type of antibodies found and whether levels are stable, rising or falling, it’s possible to find out when the infection took place.

What happens if I have toxoplasmosis?

If the test suggests a current or recent infection, the blood must be sent on from the local laboratory to the Toxoplasma Reference Laboratory for further testing. 

If further tests confirm that you have a current or recent infection (acute toxoplasma infection), you may have further tests to help assess the risk of passing the infection on to your baby.

If I have toxoplasmosis, how likely is it that my baby will be infected?

If you have toxoplasmosis, the risk of your baby getting infected largely depends on when you became infected during your pregnancy. 

Toxoplasma infection in early pregnancy is less likely to spread to your baby, but if problems do develop, they are likely to be more serious. If you become infected later on in pregnancy, this is more likely to spread to your baby, but any problems that do develop are likely to be less severe.  

How do they find out if the baby is infected before birth?

Further tests can be carried out to find out if the baby is infected, although the tests will not show how the infection may have affected the baby. A doctor can explain the risks and benefits of doing these tests.

You may have an ultrasound scan, although this may not be able to confirm a diagnosis. 

You may also have amniocentesis or cordocentesis. In amniocentesis, your doctor will take a sample of the amniotic fluid that surrounds your baby. This is done using a thin needle inserted into your tummy. Cordocentesis is a technique where a sample of the baby’s blood is removed from the umbilical cord. 

These tests are normally carried out after 15 weeks of pregnancy. The amniotic fluid or blood from the umbilical cord is then tested at the Toxoplasma Reference Laboratory using a range of specialised tests, including polymerase chain reaction (PCR). It usually takes about 2 to 5 days for the results to come back. 

It’s important to know that these tests are not completely safe for your baby because there is a small risk of miscarriage. Your doctor will talk to you about this before getting your consent (permission). 

If the results are positive, your doctors will do an ultrasound scan, which will show if the baby has been significantly affected, such as hydrocephalus (water on the brain). If the scan doesn’t show any serious problems, this can be reassuring, but unfortunately it does not completely rule out the possibility that the baby is both infected and affected.

Terminating the pregnancy

If tests show that the infection has caused serious problems in the baby, you may be offered a termination. This is a highly personal choice. You should be given all the information you need to decide what is best for you. 

Find out more about terminating a pregnancy for medical reasons

How is toxoplasmosis treated in pregnancy?

If you do get toxoplasmosis in pregnancy, you may be offered antibiotics. The antibiotics you need will depend on how far along your pregnancy is. This treatment is designed to reduce the chance of you passing the infection to your unborn baby.
If tests suggest that your baby has been infected, you will be offered antibiotic treatment to prevent or reduce problems for your baby. With some of these antibiotics, you will also need to take a supplement called calcium folinate. This will help your body make folic acid, which is essential for the healthy development of your baby. 

You will probably take these drugs for the rest of your pregnancy. 

How will my baby be affected when they are born?

If you get toxoplasmosis just before or during your pregnancy, your baby will be tested for the infection after they are born. They will also be checked for any problems related to the infection. 

This information can be difficult to read but try to remember that these effects are rare. It's estimated that only 1 in 10,000 babies is born with toxoplasmosis in the UK. 

Most babies with toxoplasmosis seem healthy at birth. But many will have some health problems months or even years later. These may include: 

  • eye problems 
  • hearing problems 
  • seizures 
  • learning difficulties 
  • delayed growth. 

Treatment can help reduce the chance of these problems happening. 

Some babies with toxoplasmosis have signs of a severe infection when they are born. For example, they may have:

  • damage in the eye
  • an enlarged liver and spleen
  • jaundice (yellowing of the skin and eyes)
  • pneumonia.  

If a baby was infected early in pregnancy, they may be blind or have other problems related to their development in the womb. Sadly, some babies are stillborn or die a few days after birth.  

Will my baby have treatment after they are born?

Yes. Doctors will take a blood sample from your baby to find out if they are infected and check for signs of neurological (brain) damage and eye problems. They will also carry out all the usual general health checks, including the newborn physical examination.  

Treatment for babies who have been infected with toxoplasmosis

If your baby is infected, they might need antibiotic medicine for their first year, until their immune system has developed enough for them to fight the infection. 

Your baby will have a blood test every few months until they are 1 to monitor their progress. 

Is it safe to breastfeed if I have toxoplasmosis?

Yes. Toxoplasmosis cannot pass through your breastmilk to your baby. 

Breastfeeding has great benefits for your baby. It can help strengthen their immune system, which helps them to fight infection. Your milk also has antibodies, hormones and other factors needed for growth and development. 

If you have cracked and bleeding nipples, or you have mastitis, you may have some blood in your breast milk. If this is the case, it is possible that toxoplasmosis could be in that blood and infect the baby. But this is highly unlikely and there are no recorded cases of this happening. Talk to your GP, midwife or health visitor if you have any pain during breastfeeding. 

Do not breastfeed if you have toxoplasmosis and you are taking pyrimethamine (one of the antibiotics sometimes used to treat toxoplasma infection). Talk to your GP about changing your medication before breastfeeding. 

Will I pass the infection on to my baby if I get pregnant again?

No. If you have had toxoplasmosis in pregnancy, you will not be at risk of passing the infection on to your baby in a future pregnancy, as long as your immune system is healthy. 

More support and information

If you need someone to talk to, our midwives are available to help. You can call our pregnancy line for free on 0800 014 7800 (Monday to Friday, 9am to 5pm), or email us at [email protected].

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Health Protection Agency (2012) Investigation of Toxoplasma Infection in Pregnancy. UK Standards for Microbiology Investigations. 5 Issue 2.2. http://www.hpa.org.uk/SMI/pdf

BMJ Best Practice (2020) Toxoplasmosis in pregnancy: what treatments work? https://bestpractice.bmj.com/info/
  
BMJ Best Practice (2020) Toxoplasmosis in pregnancy: what is it? https://bestpractice.bmj.com/info/

BMJ Best Practice (2020) Toxoplasmosis in pregnancy: what treatments work? https://bestpractice.bmj.com/info/

Sue Macdonald, Gail Johnson, Mayes’ Midwifery. Edinburgh: Bailliere Tindall Elsevier, 2017), p.765-767

Centers for Disease Control and Prevention. (August 2021) Toxoplasmosis https://www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/maternal-or-infant-illnesses/toxoplasmosis.html

British National Formulary. Pyrimethamine. https://bnf.nice.org.uk/drug/pyrimethamine.html

Review dates
Reviewed: 13 October 2021
Next review: 13 October 2024