Pertussis (whooping cough) vaccine in pregnancy

Key vaccine facts

Why is this vaccine recommended for pregnant women?

In 2012 the UK experienced a nationwide outbreak (epidemic) of pertussis (whooping cough), a highly infectious disease that can cause serious complications including death, especially in young babies. In 2012 there were over 9,300 cases in England alone – more than ten times as many as in recent years. The causes of this are not clear. In the years since 2012 there has been a fall in cases, but numbers are still high compared to the years before the 2012 epidemic (see the graph at the bottom of this section). 14 babies under three months old died of pertussis in 2012, and another 18 died between 2013 and 2016. There were no deaths from pertussis in 2017, and no deaths in the first nine months of 2018. Babies under three months of age are most vulnerable to severe disease.

Vaccination of mothers can protect babies from pertussis. In the UK, a temporary programme began in October 2012 to offer pertussis vaccination to pregnant women. In July 2014 it was recommended that this programme should continue for at least 5 more years, owing to continuing high levels of pertussis in the UK. A similar programme is now offered in the US, Australia, and some other European countries. Around 70% of pregnant women in England currently receive the whooping cough vaccine. Out of the 18 babies who have died of pertussis since the start of 2013, 16 were born to mothers who had not been vaccinated against pertussis.

In this film, experts talk about why it is important for pregnant women to be vaccinated against pertussis. Since the film was made the UK government advice has changed. Pregnant women can now be vaccinated any time after 16 weeks of pregnancy (rather than just in the third trimester). Pregnant women will usually be told about the vaccine at their routine 20-week scan.

Why are newborn babies vulnerable?

In the UK babies currently get protection against whooping cough as a result of their routine vaccinations at 2, 3 and 4 months (the 6-in-1 vaccine). However, newborn babies are vulnerable until they have had at least 2 doses of the vaccine (i.e. until they are 3-4 months old). Babies under 3 months old are at greatest risk of complications and death from pertussis.

Vaccinating babies at birth does not offer them the best protection against pertussis, for two reasons. Firstly, newborn babies’ immune systems do not respond well at this age to the first dose of pertussis vaccine. Secondly, vaccination does not offer immediate protection. It takes several days to respond to the vaccine, and at least two doses of vaccine are needed to give high levels of protection.

Even people who were vaccinated against pertussis as babies can catch the disease. It can then be passed on to those they come into contact with, including newborn babies. In years like 2012-2016 when there were thousands of cases of pertussis, newborn babies are at a much higher risk of catching this life-threatening disease. Read a BBC news article about an Australian mother who passed pertussis on to her newborn baby .

How does vaccination of pregnant women help to protect their babies?

Vaccination during during weeks 16 to 32 of pregnancy helps the mother make antibodies to fight pertussis. It takes about two weeks for antibody levels to peak. These antibodies are then transferred through the placenta to the baby, who then has the mother’s own protection against the disease in their blood right from birth. Very small quantities of pertussis antibodies may also be transferred to the baby through breast milk. In addition, the mother is protected against catching pertussis and passing it to her newborn baby. Pregnant women can be vaccinated any time up until they go into labour, but vaccination before week 32 is advised because it takes about two weeks for antibodies to pass across to the unborn baby. Overall, vaccinating women during pregnancy is the best way to protect newborn babies who are too young to be vaccinated themselves.

The protection offered by the mother’s antibodies lasts only a few months. It is therefore important for babies to get their routine immunisations at 2, 3 and 4 months so that they continue to be protected (the 6-in-1 vaccine).

It is recommended that women have the pertussis vaccine in each pregnancy, even if they have been vaccinated in a previous pregnancy.

What vaccine is given to pregnant women?

The vaccine offered to pregnant women in the UK is called Boostrix-IPV. This is also used as a pre-school booster vaccine, and protects against diphtheria, tetanus and polio as well as pertussis. The vaccine does not contain any live bacteria or viruses, and cannot cause any of the diseases it protects against.

Boostrix-IPV can safely be given to pregnant women at the same time as the flu vaccine. See the Patient Information Leaflet .

Click here for an accessible text version of this graph

Source: Public Health England Archive and Public Health England pertussis reports

Ingredients

Apart from the active ingredients (the antigens), the vaccine used in the UK (Boostrix-IPV) contains very small amounts of:

Aluminium, which strengthens and lengthens the immune response to the vaccine
Medium 199, a stabiliser containing amino acids, mineral salts, vitamins and other substances
sodium chloride (salt)
Polysorbate, used as an emulsifier (to hold other ingredients together)

Growing the active ingredients for the vaccine:

The polio part of the vaccine is grown in the laboratory using animal cell strains

Other brands of pertussis-containing vaccine offered to pregnant women in other countries may contain different ingredients. If you are not in the UK, ask for the Patient Information leaflet for the vaccine you are offered.

Side effects

Very common side effects in adults (affecting more than 1 in 10 people at each dose):

redness, pain and swelling at the injection site
headache
tiredness
generally feeling unwell

Common side effects in adults (affecting up to 1 in 10 people at each dose):

fever up to 39°C
bruising, itching, warmth, numbness or a lump at the injection site
stomach pain, feeling sick or being sick

Uncommon side effects (affecting up to 1 in 100 people at each dose):

fever over 39°C
swelling of the vaccinated limb
chills, pain, itching, dizziness or sleepiness
joint or muscle pain
lack of appetite
numb or tingling hands or feet
flu-like symptoms
cold sores
swollen glands
asthma

For rarer side effects (affecting fewer than 1 in 1000 people), see the Patient Information Leaflet for Boostrix-IPV .

Anaphylaxis

As with any vaccine, medicine or food, there is a very small chance of a severe allergic reaction (anaphylaxis). Anaphylaxis is different from less severe allergic reactions because it causes life-threatening breathing and/or circulation problems. It is always extremely serious but can be treated with adrenaline. Health care workers who give vaccines know how to do this. In the UK between 1997 and 2003 there were a total of 130 reports of anaphylaxis following ALL immunisations. Around 117 million doses of vaccines were given in the UK during this period. This means that the overall rate of anaphylaxis is around 1 in 900,000.

More information on side effects

Reactions listed under ‘possible side effects’ or ‘adverse events’ on vaccine product information sheets may not all be directly linked to the vaccine. See Vaccine side effects and adverse reactions for more information on why this is the case.

If you are concerned about any reactions that occur after vaccination, consult your doctor. In the UK you can report suspected vaccine side effects to the Medicines and Healthcare products Regulatory Agency (MHRA) through the Yellow Card Scheme . You can also contact the MHRA to ask for data on Yellow Card reports for individual vaccines . See more information on the Yellow Card scheme and monitoring of vaccine safety.

More information about the vaccine

Pertussis vaccination for adults travelling abroad to visit newborn babies

Some countries recommend that all the close contacts around a newborn baby are vaccinated against pertussis. This means that some UK residents travelling to other countries to visit newborn babies are being asked by family or friends to get vaccinated against pertussis before they go. This approach is often called ‘cocooning’.

There is some evidence that cocooning will help to prevent transmissions from family members to the newborn baby, but it is a difficult programme to implement nationally. Vaccination of mothers in pregnancy is the most effective way to protect newborn babies against pertussis. In addition to the UK, many countries now offer pertussis vaccination during pregnancy (including Australia and the US).

Travellers planning to visit friends and relatives who have just had a baby can check that the mother has had a pertussis vaccine before they visit. The UK government does not officially recommend that adult UK travellers should get vaccinated against pertussis in these circumstances, so it is not generally available as a travel vaccine, although it may be possible to obtain the vaccine privately. (Babies and children over 4 months of age who are travelling will already be protected by the 5-in-1, 6-in-1 and/or pre-school booster vaccines.)

For more information, see the NaTHNaC website . NaTHNaC (the National Travel Health Network and Centre) is commissioned by Public Health England to provide up to date and reliable information on travel vaccines for UK travellers.

Does the vaccine work?

In July 2014 The Lancet published a study by Public Health England which showed that babies born to vaccinated mothers had high levels of protection against pertussis. These babies had a 91% reduction in the risk of pertussis disease in their first weeks of life when compared with babies whose mothers had not been vaccinated. A second Public Health England study published in 2016 confirmed this. In 2017, a US study of nearly 150,000 pregnant women showed a similar result. Since the disease reached its peak in the UK in 2012, the greatest decrease in pertussis cases has been in babies under six months of age. This also shows that vaccination during pregnancy is having a significant effect.

In April 2016 the UK’s Department of Health updated its advice on the best time for pregnant women to get the pertussis vaccine. The vaccine is now recommended any time between week 16 and week 32 of pregnancy. Before April 2016 pregnant women were advised to get the vaccine in the third trimester (between week 28 and week 32), which was thought to be the best time for antibodies to be made and passed from the mother to the baby across the placenta. The change in advice was based on a new study by Swiss researchers which showed that more antibodies crossed from the mother to the baby when the pertussis vaccine was given earlier in pregnancy.

Is the vaccine safe?

There are no safety concerns about the use of the vaccine in pregnancy, and there is considerable experience of its use both in the UK and the United States. Boostrix-IPV has been used extensively in Australia, New Zealand and other countries. These combination vaccines are being used because a single pertussis vaccine is not available. Many millions of doses have been given to children in recent years without any concerns about harm. Boostrix-IPV contains low-dose diphtheria and tetanus, which means that the rate of side effects is lower than with the 6-in-1 vaccine, for example.

A large safety study involving over 20,000 vaccinated pregnant women , undertaken by the UK's Medicines and Healthcare products Regulatory Agency (MHRA), has found no risks in pregnancy from Repevax, which was the vaccine used for this programme until summer 2014. Repevax is one of the two pre-school booster vaccines used in the UK, and is very similar to Boostrix-IPV but made by a different manufacturer. Similar vaccines have also routinely been given to pregnant women in the USA over the last few years without concerns (see information from the US Centers for Disease Control and Prevention ). Although there is so much experience of the use of the vaccine, it was not studied as part of a clinical trial in pregnancy. This is why the manufacturer’s information leaflets for both Repevax and Boostrix-IPV state that the vaccine is 'not recommended for use in pregnancy' or 'should be used during pregnancy only when clearly needed'.

A large Australian study of nearly 82,000 babies looked at rates of autism in babies born to women who had been vaccinated against whooping cough in pregnancy. (The vaccine used in Australia is slightly different from the one used in the UK; it protects against diphtheria and tetanus as well as whooping cough, but not polio.) The study found that these babies were no more likely to have autism than those born to women who had not been vaccinated against whooping cough in pregnancy.