Infections that may affect your baby

Rubella

Rubella (or German measles) can seriously affect your baby’s sight and hearing, and cause brain and heart defects in your baby if you catch it in the first four months of pregnancy. All children are now immunised against rubella at 12-15 months, and again before they start school. If you’re not immune and you do come into contact with rubella, tell your maternity team at once. Blood tests will show whether you have been infected, and you will be able to think about what action to take.

Sexually transmitted infections

Sexually transmitted infections (STIs) are common and there are often no symptoms, so you may not know if you have one. However, many STIs can affect your baby’s health during pregnancy and after birth. If you have any reason to believe that you or your partner could have an STI that was not diagnosed before pregnancy, go for a checkup as soon as possible. You can ask your maternity team or, if you prefer, go to a hospital clinic for STIs. You will be guaranteed confidentiality. Use the service search box on the right to find a local sexual health and genitourinary medicine (GUM) clinic.

Hepatitis B

Hepatitis B is a virus that infects the liver. Many people with hepatitis B, even if they show no sign of illness, can be carriers and may infect others. The virus is spread by sex with an infected person without using a condom and by direct contact with infected blood. If you are a carrier, or are infected during pregnancy, you can pass the infection to your baby at birth. All pregnant women are offered a blood test for hepatitis B as part of their antenatal care. Babies who are at risk can be immunised at birth to prevent infection.

Hepatitis C

Hepatitis C is a virus that infects the liver. The virus is transmitted by direct contact with infected blood. This can be as a result of sharing blood-contaminated needles and drug-injecting equipment; or receiving a blood transfusion in the UK prior to September 1991, or blood products prior to 1986. It can also be transmitted by receiving medical or dental treatment in countries where hepatitis C is common and infection control may be poor; or by sexual intercourse with an infected partner. Many people with hepatitis C may have no symptoms and be unaware that they have been infected. If you have hepatitis C, you may pass the infection to your baby, although the risk is much lower than with hepatitis B or HIV. This cannot be prevented at present. Your baby can be tested for hepatitis C and, if your baby is infected, he or she can be referred for specialist assessment.

Herpes

Genital herpes infection can be dangerous for a newborn baby. It can be caught through genital contact with an infected person or from oral sex with someone who has oral herpes (cold sores). Initial infection causes very painful blisters or ulcers on the genitals. Less severe recurrent attacks usually occur for some years afterwards. If you, or your partner, are infected, use condoms or avoid sex during an attack. Avoid oral sex if you or your partner have cold sores or active genital herpes. Tell your maternity team if either you or your partner have recurring herpes or develop the symptoms described above. If your first infection occurs in pregnancy there is a treatment available, although its use is
controversial. If the infection is active during labour, a caesarean section may be recommended to reduce the risk of transmission to the baby.

Chickenpox

If you think you may not be immune to chickenpox get a test to find out, as catching it while pregnant is dangerous for you and your baby. Around 95% of women are immune to chickenpox. If you have never had chickenpox, or are unsure, and come into contact with a child or adult who has it, speak to your maternity team. A blood test will establish if you are immune. Chickenpox infection in pregnancy can be dangerous for both mother and baby, so seek advice early.

Toxoplasmosis

This infection can damage your baby if you catch it during pregnancy, so take precautions (see infections transmitted by animals, further down this page). Most women have had the infection before pregnancy and will be immune. If you feel you may have been at risk, discuss it with your maternity team. If you do catch toxoplasmosis while you’re pregnant, treatment is available.

Parvovirus B19 (slapped cheek disease)

Parvovirus B19 infection is common in children and causes a characteristic red rash on the face, so it is often called ‘slapped cheek disease’. Although 60% of women are immune to this infection, parvovirus is highly infectious and can be harmful to the baby. Any pregnant woman who comes into contact with someone who is infected should seek advice from her doctor. Immunity can be checked with a blood test. In most pregnant women who are infected with parvovirus the baby is not affected.

Group B streptococcus

Group B Streptococcus (GBS) is a bacterium carried by up to 30% of people but causes no harm or symptoms. In women it is found in the intestine and vagina and causes no problem in most pregnancies.

In a very small number it infects the baby, usually just before or during labour, leading to serious illness. This is more likely if your labour is premature, your waters break early, you have a fever during labour, you currently carry GBS or if a previous baby had a GBS infection. If appropriate, antibiotics given through a vein during labour will usually prevent infection of the baby. It is possible to be tested for GBS late in pregnancy. Routine testing is not recommended in the UK because there is insufficient evidence to support it. If you’re concerned about GBS, discuss it with your maternity team.

HIV and AIDS

Current evidence shows that an HIV-positive mother in good health and without symptoms of the infection is unlikely to be adversely affected by pregnancy but has the potential to pass it on to her baby. If you’re HIV positive, talk to your doctor about your own health and the options open to you, or use our list of useful organisations to find advice and counselling. It’s possible to substantially reduce or eliminate the risk of transmitting HIV to your baby during pregnancy and after birth through medications and other steps. You should be offered and recommended a named confidential HIV test as part of your routine antenatal care. Your maternity team will discuss the test with you before it is carried out, and counselling will be available afterwards to explain the result and the implications if it is positive. You can also go to a genitourinary medicine clinic for an HIV test and advice. Use the service search box on the right to find a local sexual health and genito-urinary medicine (GUM) clinic.

Infections transmitted by animals

Cats’ faeces may contain an organism that causes toxoplasmosis, a disease which can damage your baby.

1. Avoid emptying cat litter trays while you’re pregnant, or, if no one else can do it, use disposable rubber gloves. Trays should be cleaned daily and filled with boiling water for five minutes.
2. Avoid close contact with sick cats and wear gloves when gardening - even if you don’t have a cat – in case the soil is contaminated with faeces.
3. Wash your hands and gloves after gardening.
4. If you do come into contact with cat faeces, make sure you wash your hands thoroughly.
5. Follow general food hygiene rules. Lambs and sheep can be a source of an organism called Chlamydia psittaci that is known to cause miscarriage in ewes. They also carry Toxoplasmosis. Avoid lambing or milking ewes and all contact with newborn lambs. If you experience flu-like symptoms after coming into contact with sheep, tell your doctor.