Vaccination in pregnancy explained: protecting mother and baby

Why vaccinate during pregnancy

Vaccination in pregnancy has two goals: protecting the mother, and protecting the baby in the first weeks of life. Some infections, such as flu, can be more serious in pregnancy because the body's immune system works differently and the lungs and heart are under extra strain. At the same time, newborn babies cannot be given most of their own vaccines until they are a few weeks or months old, leaving them vulnerable early on. When a pregnant woman is vaccinated, her body makes protective antibodies that cross the placenta to the baby. This gives the baby a head start of protection during the risky first weeks, until they can begin their own childhood vaccinations.

The whooping cough vaccine

Whooping cough (pertussis) is a serious infection that can be life-threatening for very young babies, causing severe coughing fits and difficulty breathing. Because babies do not start their own whooping cough vaccinations until they are a couple of months old, the UK offers the vaccine to pregnant women, ideally from around the middle of pregnancy. The antibodies the mother makes pass to the baby before birth, protecting them in those first vulnerable weeks. The vaccine used also protects against other infections. It is offered in every pregnancy, even if the woman was vaccinated in a previous one, because the passed-on protection is strongest when the vaccine is given during that particular pregnancy.

The flu vaccine

Flu is not just a heavy cold — for pregnant women it can lead to serious complications, including chest infections and, occasionally, hospital admission, and it can raise the risk of problems for the baby. Because of this, the flu vaccine is recommended for pregnant women at any stage of pregnancy, and it is offered free each autumn and winter as flu circulates. The vaccine is an inactivated one, meaning it cannot cause flu, and it is considered safe at any point in pregnancy. As with whooping cough, some protection also passes to the baby. Being vaccinated helps keep the mother well through pregnancy and lowers the chance of flu spreading to the newborn.

The RSV vaccine

Respiratory syncytial virus, or RSV, is a common cause of coughs and colds, but in young babies it can cause bronchiolitis — an infection of the small airways that can make breathing difficult and sometimes needs hospital care. The UK now offers an RSV vaccine in pregnancy, given in the later part of pregnancy, so that protective antibodies pass to the baby before birth. This helps protect newborns from severe RSV infection during their first months, when they are most at risk. Offering the vaccine in pregnancy is a newer part of the UK programme and is aimed squarely at reducing serious RSV illness and hospital admissions in the youngest babies.

Safety and getting vaccinated

The vaccines offered in pregnancy have been carefully assessed and are recommended precisely because the benefits to mother and baby outweigh the risks. The vaccines used are not live vaccines, so they cannot cause the infections they protect against. Millions of pregnant women have received them, and side effects are usually mild and short-lived, such as a sore arm or feeling a little unwell for a day or two. These vaccines are usually offered through your midwife, GP surgery or maternity service, and it is worth asking about them at your antenatal appointments. If you have questions or concerns, your midwife or doctor can talk them through and help you decide.