Infants under the age of three months are at increased risk of severe complications of pertussis infection, including death. There is good evidence that pertussis vaccination during pregnancy is associated with reduced rates of neonatal pertussis infection and its sequelae. Ongoing protection is then provided via infant pertussis vaccination commencing at two months of age.
The Joint Committee on Vaccination and Immunisation recommends that all pregnant women in the UK are vaccinated with a combined, inactivated tetanus/diphtheria/acellular pertussis/polio (Tdap-IPV) vaccine (usually Boostrix IPV®) between 16 and 32 weeks of gestation. Women may still be immunised after week 32 of pregnancy until delivery, but this may not offer as high a level of passive protection to the infant.
Pertussis vaccination is generally offered at a stage of pregnancy where fetal structural development is complete and will therefore not increase the risk of structural congenital malformation in the infant. There is very robust evidence that pertussis vaccination has no adverse effects on pregnancy outcomes that could hypothetically be affected by exposure in the second and third trimesters (stillbirth, intrauterine growth restriction, preterm delivery, neonatal complications), with some studies suggesting that these events are less likely following vaccination. While slightly increased rates of chorioamnionitis following pertussis vaccination have been noted, the clinical significance of this is unclear as higher rates of expected sequelae (preterm delivery or NICU admission) have not been observed. Pregnancy outcomes following first trimester exposure to pertussis vaccines have not been well-studied as vaccination at this stage of pregnancy is uncommon. However, the limited available data raise no concern of increased risks of miscarriage or congenital anomaly and there are no known fetal risks relating to use of any non-live vaccine at any stage of pregnancy.
Exposure to pertussis vaccine at any stage in pregnancy would not be regarded as medical grounds for termination of pregnancy or any additional fetal monitoring. However, other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.
For information on use of the Tetanus/diphtheria/polio vaccine (Td-IPV) in pregnancy please refer to the separate monograph.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.