Knowledge gaps and research priorities regarding vaccination in pregnancy: A Canadian perspective from the prevention of infections in the maternal-infant dyad (PRIMED) consortium

Vaccination in pregnancy is a safe and effective method for protecting both the pregnant woman/person and their infant from communicable diseases. Despite a growing body of evidence of the benefits of vaccination during pregnancy and the widespread introduction of vaccines during pregnancy for influenza, pertussis, and COVID-19, there is no national research agenda in Canada to guide funding and research. We sought to create a roadmap for Canadian vaccination in pregnancy research. During 2017-2023, working with immunization stakeholders using in-person and virtual workshops and online surveys, we identified priorities for Canadian research on vaccination in pregnancy. Stage one (2017-18) included a workshop, followed by a survey, regarding 39 pertussis-related research gaps and priorities, and included researchers, immunization decision-makers, frontline immunizers, policymakers, and research funders. Stage two (2022) was a cross-sectional survey across eight diseases and seven research approaches sent to a similar group. During stage three (2023), we held three expert workshops focusing on three priority areas identified during stage two, including cytomegalovirus (CMV), group B streptococcus (GBS), and respiratory syncytial virus (RSV). Our work identified several research priorities, including SARS-CoV-2, CMV, GBS, and RSV vaccine trials and immunologic studies, and the need for research into the attitudes of pregnant women and other pregnant people, prenatal care providers, and frontline immunization providers toward vaccination during pregnancy. As such, we recommend focusing vaccination in pregnancy research toward these high-impact areas. These results define a roadmap for a cohesive research strategy around vaccination in pregnancy.