Optimising Timing of whooping cough Immunisation in MUMs
Follow up completed, laboratory analysis in progress.

Aim of the study: To investigate the impact of timing on the antibody response to whooping cough vaccination in pregnancy
Inclusion and exclusion criteria
Inclusion:
- Pregnant and not yet having received pertussis vaccination
- Willing and able to comply with study procedures and provide informed consent
- Documentation of a 20-week anomaly scan with no life limiting congenital anomalies identified
- At ≤23+6 gestational weeks
Exclusion:
- Age less than 16 years
- Confirmed or suspected pertussis in previous five years
- Known diagnosis of immune deficiency
- Receiving immunosuppressive medication within six months of enrolment in the study (this does not include inhaled or topical steroids)
- In the opinion of the investigator is unlikely to complete follow up
What participating in the study involves?
Participants will be recruited in pregnancy prior to receiving a pertussis containing vaccine and will be randomised into one of three groups receiving the vaccine at three different time periods: ≤23+6, 24-27+6 and 28-31+6 weeks of gestation. Women will be involved in the study from the time of enrolment at around 20 weeks to the time of delivery (a period of around 20-22 weeks in total), and their infants will be involved in the study from birth until the age of 5 months (around 5 months in total).
Each maternal participant will have four study visits: screening, vaccination, 14 days following vaccination and at delivery, and infants will have a study visit 28-70 days after their third primary vaccination (around 5-7 months of age). Two sites will be involved in a sub-study investigating whooping cough antibody in breastmilk after vaccination and participants taking part in this will have two additional study visits following delivery. (Table 1)
Table 1: Summary of study visits
Visit Number | Screening visit | Vaccination visit | Follow up visit | Delivery visit | Breastmilk sub-study visit 1* | Breastmilk sub-study visit 2* | Infant visit |
Timing | At or before 23+6 weeks | According to study allocation | V+14 (+/- 2) | Delivery | <48 hours from delivery | D+14(+/- 2) | 28-70 days following third pertussis vaccination |
Activity | Screening & enrolment
|
Maternal blood sampling and vaccination. Diary card provided.
Questionnaire. |
Maternal blood sampling. Diary card collected. | Maternal blood and cord blood sampling | Colostrum sampling | Collection of breastmilk sample | Infant blood sampling
Collection of breastmilk sample if still breastfeeding |
Results (if applicable)
Not yet available.