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Lessons Learned From the COVID-19 Vaccines International Pregnancy Exposure Registry: Insights for Designing and
Diego F Wyszynski1, Cheryl Renz2
1Thermo Fisher Scientific Inc., London, UK.
Insights
The COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) successfully collected safety data on COVID-19 vaccines in pregnant women. Lessons learned will improve future pregnancy vaccine safety studies.
Area of Science:
- Obstetrics and Gynecology
- Vaccinology
- Epidemiology
Background:
- Pregnant individuals face higher COVID-19 risks but lacked initial vaccine trial data.
- The COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) was created to gather pregnancy-specific vaccine safety information.
- This study details operational and methodological insights from the C-VIPER implementation.
Purpose of the Study:
- To summarize key lessons from the implementation of the COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER).
- To identify operational, methodological, and scientific insights for future pregnancy safety studies.
- To assess the feasibility of a multinational, web-based pregnancy registry during a pandemic.
Main Methods:
- A prospective, international, noninterventional, postmarketing cohort study.
- Utilized a web-based platform for enrolling pregnant women vaccinated against COVID-19.
- Collected longitudinal data on maternal, pregnancy, birth, neonatal, and infant outcomes.
Main Results:
- Registry implementation faced challenges like vaccine hesitancy and evolving vaccination schedules.
- Despite difficulties, C-VIPER proved the feasibility of large-scale international pregnancy registries in emergencies.
- Highlighted critical methodological considerations for future postmarketing vaccine safety research in pregnancy.
Conclusions:
- C-VIPER enhanced the evidence on COVID-19 vaccination in pregnancy.
- Provided valuable lessons for designing and executing future pregnancy registries.
- Emphasized the need for early planning, flexible protocols, strong recruitment/retention, and data quality improvements.
Background:
Pregnant women are at increased risk of severe illness from COVID-19, yet they were excluded from the initial clinical trials of COVID-19 vaccines, resulting in limited pregnancy-specific safety data. The COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) was established to prospectively collect safety and birth outcome data following COVID-19 vaccination during pregnancy. This article summarizes key operational, methodological, and scientific lessons from implementation of the registry.
Methods:
The C-VIPER was designed as an international, noninterventional, postmarketing cohort study using a web-based platform to enroll pregnant women exposed to COVID-19 vaccines and collect longitudinal maternal, pregnancy, birth, neonatal, and infant outcome data. Registry implementation, recruitment, retention, questionnaire design, comparator selection, data completeness, and evolving vaccination patterns were reviewed to identify lessons relevant to future pregnancy safety studies.
Results:
Implementation during a global pandemic presented substantial challenges, including uncertainty regarding vaccine acceptance and study participation among pregnant women, widespread misinformation and vaccine hesitancy, evolving vaccination regimens, recruitment and long-term retention difficulties, and limitations in questionnaire design and data completeness. Despite these challenges, the C-VIPER demonstrated the feasibility of conducting a large-scale multinational, web-based pregnancy registry under emergency conditions and highlighted important methodological considerations for future postmarketing vaccine safety studies in pregnancy.
Conclusions:
The C-VIPER contributed to the broader evidence base evaluating COVID-19 vaccination during pregnancy and provided important lessons for the design and implementation of future pregnancy registries. Future studies should prioritize early planning, flexible protocol design, robust recruitment and retention strategies, careful comparator selection, and mechanisms to improve data completeness and quality.
Trial Registration:
NCT04705116, EUPAS39096.
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