Rubella Immunity in Pregnancy: Complete Guide

Rubella (German measles) is usually a mild illness, but catching it in early pregnancy can seriously harm your baby's development. That's why checking your immunity is a routine part of antenatal care in the UK, even though most adults are protected thanks to the childhood MMR vaccine.

Why rubella immunity matters in pregnancy

Rubella itself is often a minor infection in adults — a few days of a mild rash, low-grade fever and swollen glands. The real concern is what it can do to an unborn baby.

If a pregnant woman catches rubella in the first 10-12 weeks of pregnancy, there's a high chance the virus will cross the placenta and affect the baby's development. This is known as congenital rubella syndrome.
Congenital rubella syndrome can cause serious, permanent problems including hearing loss, eye problems (including cataracts), heart defects, and developmental delay.
The risk to the baby drops considerably as pregnancy progresses, but infection later in pregnancy can still cause complications, so avoiding exposure throughout pregnancy is sensible.
Thanks to the UK's long-standing MMR (measles, mumps and rubella) vaccination programme, rubella is now rare in this country, but it hasn't disappeared, and cases can still occur, particularly among people who missed vaccination.

How rubella immunity is checked

In the UK, rubella immunity is generally checked using your vaccination history rather than a blood test for most women, though testing may still happen in some circumstances.

Your midwife will ask about your MMR vaccination history at your booking appointment, usually around 8-10 weeks.
If you've had two doses of the MMR vaccine as a child, you're considered immune and no further action is usually needed.
If your vaccination history is unclear, or you were born or grew up outside the UK where MMR uptake may have differed, your midwife may discuss whether a blood test to check your antibody levels is appropriate.
If a test shows you're not immune, this will be noted in your maternity records so your team knows to be alert to any rubella exposure during your pregnancy.

If you're not immune to rubella

Finding out you're not immune can feel worrying, but there are clear, practical steps to manage it.

The MMR vaccine cannot be given during pregnancy because it's a live vaccine, so if you're found to be non-immune, vaccination is offered after you've given birth.
Getting vaccinated after birth protects you — and any future pregnancies — going forward.
MMR is safe while breastfeeding, so this shouldn't be a barrier to catching up on vaccination postnatally.
During pregnancy, if you're not immune, try to avoid close contact with anyone who has rubella, a rubella-like rash, or has recently been exposed to it.
If you do think you've been exposed to rubella while pregnant and you're not sure of your immunity, contact your midwife or GP promptly rather than waiting for your next routine appointment.

What to do if you develop a rash or feel unwell

Because rubella can look similar to other mild viral illnesses, it's not always obvious when to be concerned.

Contact your midwife or GP if you develop a rash, fever, or swollen glands during pregnancy, particularly if you know you're not immune to rubella or you've been in contact with someone who is unwell.
Try not to attend a GP surgery or antenatal clinic in person without calling ahead first, as rubella is contagious and staff will want to manage the risk of exposing others.
Your healthcare team can arrange appropriate testing and advice based on your individual circumstances and stage of pregnancy.

Frequently Asked Questions

What does it mean if I'm not immune to rubella?

It means you don't have enough antibodies to protect you from rubella infection, so if you were exposed to the virus, you could catch it. Because rubella infection in early pregnancy carries a risk of serious harm to the baby's development, being non-immune is noted in your records so your care team can advise you on avoiding exposure and can respond quickly if you do come into contact with the virus.

Can I get the MMR vaccine during pregnancy?

No, the MMR vaccine is a live vaccine and isn't given during pregnancy. If you're found to be non-immune, you'll be offered the vaccine after you've given birth, which protects you for any future pregnancies. It's safe to have while breastfeeding, so this is usually arranged before you leave hospital or at a postnatal appointment.

How is rubella immunity actually confirmed — do I need a blood test?

For most women, your midwife establishes immunity from your MMR vaccination history at booking. A blood test to check antibody levels isn't routine for everyone, but your midwife may suggest one if your vaccination history is uncertain or incomplete. If you're unsure whether you've had both doses of MMR, mention this at your booking appointment so it can be discussed.

This article is for informational purposes only and does not constitute medical advice — always speak to your midwife or GP about your own immunity status and any symptoms.

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