pertussis vaccination in pregnancy

Last edited 04/2019

Pertussis Immunisation in Pregnancy

Pregnant women should be offered a single dose of dTaP/IPV, ideally from 16 weeks to 32 weeks of pregnancy, although the vaccine can be offered after 32 weeks

• for operational reasons, vaccination should be offered from around 20 weeks, on or after the foetal anomaly scan
  • this vaccine will act as a reinforcing dose and should be offered regardless of prior vaccination status, most adults having been primed by vaccination in infancy or by natural exposure during childhood
    
    
• pertussis vaccine can be offered to pregnant women up until they go into labour. This is not the optimal time for immunisation however since antibody levels in adults peak about two weeks after a pertussis booster. Vaccine administered between 16 to 32 weeks of pregnancy is likely to maximise the levels of pertussis antibodies transferred across the placenta, thereby providing passive immunity to the unborn child
  
  
• immunisation after week 38 is unlikely to provide passive protection to the infant but would potentially protect the mother from pertussis infection and thereby reduce the risk of exposure to her infant. For women who have not received the vaccine in pregnancy, pertussis-containing vaccine can be offered in the two months following birth i.e. up until their child receives their first dose of pertussis-containing vaccine

How does immunisation in pregnancy protect the unborn child?

• via immunising pregnant women against pertussis, the antibodies produced will cross the placenta to the foetus so that when the infant is born he/she already has antibodies against pertussis
  • immunity is short-lived, diminishing over a few months
  • thus infants should still be immunised in accordance with the routine childhood immunisation schedule
  • breast-feeding is important for infants' general health but it will not by itself prevent them becoming infected with pertussis (or other infections).

Immunisation of neonates as alternative to immunisation in pregnancy (2)

• there are few studies about the immune responses of newborn infants to pertussis-containing vaccine and there is evidence to suggest that this approach may result in poorer immune responses to subsequent routine doses of vaccine, which may leave older infants more vulnerable to infection

For adults, including pregnant women, a vaccine containing low dose diphtheria and tetanus (Repevax or Boostrix-IPV) should be used to avoid the higher rate of side effects observed with full dose preparations (1)

Side effects of the vaccination (2)

• most common side effects in adults include headache, nausea, vomiting, diarrhoea, joint and muscle pain, weakness, mild fever and injection site reactions (erythema amd inflammation)
• as with all vaccines, there is a very rare possibility (approximately one in a million doses) of this vaccine causing a severe allergic reaction called anaphylaxis
• A full list of possible side effects is available in the Patient Information Leaflet (PIL) that is provided with the vaccine

Can pertussis-containing vaccine be given at the same time as influenza vaccine? (2)

• yes
• however, influenza immunisation should not be delayed in order to give pertussis-containing vaccine at the same visit. This is because pregnant women are at risk of severe illness at any stage of pregnancy from influenza

Can pertussis-containing vaccine be given at the same time as anti-D treatment? (2)

• yes

Should the pertussis vaccine be given in every pregnancy? What about women who have been immunised relatively recently? (2)

• women who become pregnant again while the programme is in place should be offered immunisation during each pregnancy
• pregnant women who have received immunisation against pertussis, tetanus, diphtheria and/or polio relatively recently should be offered immunisation. Cumulative doses may increase the likelihood of injection site reactions or fever, but this is far outweighed by the expected benefits

Check uptodate details in the The Green Book before prescribing/administering a vaccine.

Check the Summary of Product Characteristics (SPC) before prescribing/administering a vaccine.

Reference:

• 1) The Green Book. Chapter 24 - Pertussis (April 2019)
• 2) NHS Factsheet September 2012 Pertussis (whooping cough) immunisation for pregnant women.