Antenatal infectious disease screening
When you're pregnant, your midwife will offer you a screening blood test to check for HIV, hepatitis B, and syphilis infections and for susceptibility to rubella virus. As these conditions could affect your health and the health of your baby, screening is recommended to allow earlier diagnosis and treatment.
Agreeing to screening
When you’re between eight and 12 weeks pregnant, you’ll have your first antenatal appointment.
The screening blood test is part of the booking bloods offered at this appointment.
Only one blood sample is needed for all four tests:
- HIV
- hepatitis B infections
- syphilis infections
- susceptibility to rubella
Further information is available at:
The tests and your results are confidential, as is information about your pregnancy.
Susceptibility to rubella
This test checks if you’re susceptible (not immune) to the rubella virus, also known as German measles.
Most adults in Northern Ireland are vaccinated and immune (not susceptible) to the virus.
If you have had two MMR vaccinations in the past and can show evidence from your GP of your vaccination history, this will be accepted as proof of your immunity.
If you are susceptible to rubella and have not been vaccinated in the past, you should avoid contact with anyone who has rubella when you’re pregnant.
Infection with rubella in early pregnancy, could cause your unborn baby to get congenital rubella syndrome (CRS).
This can damage their:
- sight
- hearing
- brain
- heart
If you’re over four months pregnant, rubella is unlikely to affect your baby.
If you come into contact with someone who has rubella, you should tell your doctor immediately. They can arrange a blood test to check if you are infected.
Protection if you’re not immune to rubella
MMR cannot be given during pregnancy.
However, vaccination after your baby is born will protect you from infection in future pregnancies.
If your screening test shows that you're susceptible to rubella, you will be offered two doses of the MMR (measles, mumps and rubella) vaccine after your baby has been born.
The first will be offered before discharge from hospital and the second will be offered by your GP at least four weeks later.
It’s important you don’t become pregnant for a month after getting the MMR vaccine.
More information about rubella is available at:
Syphilis
This test checks if you have syphilis, a sexually transmitted infection (STI).
If you’re pregnant and have syphilis, you could pass the infection to your unborn baby during pregnancy or delivery.
This is more likely to happen in the early stages of your infection, especially if you did not get treatment.
Effects of syphilis on you and your baby
Syphilis increases the risk of:
- miscarriage
- stillbirth
- premature birth
If you’re infected with syphilis, and are not treated, there is an increased risk your baby will have congenital syphilis, a lifelong illness which can cause any of the following:
- deformed bones
- severe anaemia (low blood count)
- enlarged liver and spleen
- jaundice (yellowing of the skin or eyes)
- brain and nerve problems, like blindness or deafness
- meningitis
- skin rashes
Treating syphilis during pregnancy
If your screening test is positive for syphilis you will be reviewed by a specialist doctor from the genito-urinary medicine (GUM) clinic, who will advise on and oversee your treatment and follow-up care.
By treating syphilis early, there is less risk of permanent damage to your health and your baby’s health.
When your baby is born, a doctor may take their blood and give your baby antibiotics. They will also check for signs of congenital syphilis.
Hepatitis B
Hepatitis B is a virus that can cause liver disease.
It can be transmitted:
- through close sexual contact
- through injecting drugs
- through contact with infected blood
- from mother to baby during pregnancy
If you have the virus or become infected during pregnancy, your baby is at risk of developing congenital hepatitis B.
This is a long-term condition that can lead to liver disease.
More information about Hepatitis B is available at:
Treating hepatitis B during pregnancy
If your screening test is positive for hepatitis B you will be reviewed by a specialist doctor, a hepatologist, who will advise on and oversee your treatment and follow-up care.
They might prescribe antiviral drugs to take later in pregnancy.
Since hepatitis can be passed on through sexual contact, you will also be referred to the genito-urinary medicine (GUM) clinic, where they will offer testing to your sexual partner(s).
When your baby is born, they will be offered a hepatitis B vaccine to reduce their risk of becoming infected.
Vaccinating against hepatitis B infection
Your baby will be offered a hepatitis B vaccine at:
- birth (monovalent Hep B)
- one month old (monovalent Hep B)
- one year old (monovalent Hep B)
Under the new schedule, eligible children turning one year of age on or after 1 July 2025 will be offered the vaccine at:
- birth (monovalent Hep B)
- one month old (monovalent Hep B)
- 18 months old (six-in-one vaccine)
Your baby will also get a hepatitis B vaccination as part of the routine childhood immunisation programme.
Human Immunodeficiency Virus (HIV)
This test detects the virus that can cause AIDS. If you’re infected with HIV, you could pass the infection to your baby during:
- pregnancy
- childbirth
- breastfeeding
How HIV can affect your health
HIV damages your immune system. Without treatment, your weakened immune system can’t fight infection. Eventually you could develop AIDS.
More information about HIV and AIDS is available at:
Treating HIV during pregnancy
If your screening test is positive for HIV you will be referred to a specialist genito-urinary medicine (GUM) doctor who will advise on and oversee your treatment and follow-up care.
They will prescribe antiretroviral drugs.
Taking these won’t harm your unborn baby.
This treatment helps protect your health and reduces the risk of your baby becoming infected.
After the birth, your baby will also require treatment with antiretroviral drugs for a few weeks and a blood test to see if they are infected with HIV.