Transmissible diseases in pregnancy

During pregnancy, certain transmissible diseases can affect both you and your baby. It’s important to try and minimise the risk of picking up illnesses and manage any chronic infection you might have. 

COVID-19 and influenza

Complications from COVID-19 and influenza can be a significant risk to the health of you and your baby. If you’re unvaccinated, you have a higher chance of respiratory complications that can lead to admission to hospital. COVID-19 can increase the risk of giving birth too early and stillbirth. Vaccination can reduce the risk of severe symptoms.  

Influenza can also be dangerous during pregnancy, potentially causing complications such as pneumonia, heart damage, having your baby too early, and even stillbirth. The flu vaccine is safe to have during pregnancy and is recommended at any pregnancy stage. 


Chickenpox during pregnancy can be hazardous to both you and your baby. Let your doctor or midwife know If you've never had chickenpox or been exposed to the virus because this can mean you are at a higher risk of complications from the virus. Chickenpox during pregnancy can cause foetal varicella syndrome in the first 28 weeks of pregnancy. This can cause skin scarring, eye problems, limb differences, and brain issues in your baby. 

Hand, Foot, and Mouth (HFM) disease

It’s rare for adults to get HFM, but it can cause a miscarriage if contracted during pregnancy. Be careful about hand hygiene, and sharing eating or personal hygiene items like towels, especially if you have an older child attending daycare. 

Human Parvovirus B19 (slapped cheek or fifth disease)

Human parvovirus B19 is another infection that can be common in daycare settings. There is a small risk of miscarriage, or your baby developing severe anaemia if you are infected with human parvovirus B19 before 20 weeks of pregnancy.  

Cytomegalovirus (CMV)

CMV infections are also common in areas where there are lots of young children, like daycare. It can cause loss of hearing and vision, learning difficulties, and epilepsy in unborn babies. Make sure to wash your hands before and after eating, changing nappies, and contact with children to prevent the spread. 


Listeria is often found in certain foods that: 

  • are ready to eat off the shelf 
  • are processed by slicing, chopping, or shredding after cooking 
  • need to be refrigerated 
  • don’t have any preservatives 
  • will generally spoil after 5 days. 

You’ll find that this includes a lot of common food items, including prepackaged salads and vegetables, cooked and packaged meats like ham slices, smoked fish, and soft cheeses. 

Listeria is uncommon, but there are outbreaks in the community from time to time. It can cause miscarriage, stillbirth, premature birth, and severe illness in newborn babies. See Food safety for proper food hygiene practices to reduce the risk of listeria.

Group B streptococcus (strep)

While usually harmless, Group B strep can infect your baby as they pass through the vagina during birth. Group B strep infection can lead to serious illness in babies including breathing difficulties and meningitis. If you have the group B strep bacteria, you’ll be given antibiotics during labour to lower the risk. 

See the Tests and Scans during Pregnancy section to learn more about Group B streptococcus testing.


Toxoplasmosis is an infection caused by parasites found in animals, especially cat poo. Infection during pregnancy can harm your baby and cause brain damage, eye and spleen disorders, or even stillbirth. Avoid things like changing the cat litter and contact with outdoor sandpits as well as making sure to wash your hands and food well. 

Hepatitis B and C

Hepatitis B and C can be transmitted to your baby during pregnancy, leading to premature birth and liver damage. Early screening and vaccination for hepatitis B are essential before getting pregnant. The likelihood of transmission is low, and treatment will be given to you and your baby after birth. 

Chlamydia, Gonorrhoea, and Syphilis

Chlamydia, gonorrhoea, and syphilis are common infections spread by sexual contact. Chlamydia and gonorrhoea transmitted during pregnancy can cause infections in newborn babies, while syphilis can lead to life-threatening infections, premature birth, and multiple organ problems. 

You’ll be tested for sexually transmitted infections throughout your pregnancy in your routine blood and urine tests. Treatment is easy and involves a course of antibiotics. 


This infection is caused by a parasite, leading to premature birth and low birth weight if left untreated. Fortunately, it's easily treatable with antibiotics. 

Human Papillomavirus (HPV)

Genital warts from an HPV infection might show up more while you’re pregnant, but the risk of transmitting HPV to your baby is low. The cervical screening test is safe to do before, during, and after pregnancy and can help find strains of HPV that cause cervical cancer. Consult your healthcare provider if you have concerns about HPV or genital warts. 


Herpes can happen around the mouth and on the genitals. There is a risk of transmitting herpes to your baby during birth if you are having a virus outbreak, but this can be managed with support from your doctor or midwife. 

Herpes sores on the mouth, known as cold sores, are the biggest risk when it comes to giving herpes to a newborn baby. Well-meaning friends and family might want to give your newborn a big kiss and cuddle, but this can unknowingly spread the herpes virus and cause severe illness. Newborn babies who get the herpes virus are at risk of infections of the eyes and throat, nerve damage and even death from complications of the illness. 

It's very important to make sure friends and family are not kissing your newborn baby, and following good hygiene habits, like handwashing, to stop the spread.  

HIV (human immunodeficiency virus)

If you have HIV, treatment using Antiretroviral (ARV) medications before and during pregnancy greatly reduces the risk of transmission to your baby. Regular testing and medical care are essential. In Australia, there have been zero cases of babies born with HIV to parents who have an undetectable viral load from ARV medications. 

The current recommendations are that parents with HIV feed their baby using formula or donated breast milk, instead of breastfeeding, even if their viral load is undetectable. 

Zika virus

Zika virus can cause birth defects, such as microcephaly if contracted while pregnant. While there are no known cases in Australia, it’s important to avoid travelling to high-risk areas, like countries within the Pacific islands and Africa, while you’re pregnant. If you do travel to these countries, make sure to use mosquito repellent and take precautions to prevent pregnancy during your stay. 

Last updated Monday 6th May 2024