Tracking the progress of maternal pertussis vaccination coverage among upper-middle- and high-income countries and territories - a systematic review and modeling study.

Background: Maternal pertussis vaccination (MPV), or pertussis vaccination during pregnancy is a strategy to prevent pertussis among young infants. However, the global and regional levels of coverage and their changes over time remain poorly known. This study provides MPV coverage and trends estimations at national levels among upper-middle- and high-income countries and territories that have official MPV policy recommendations. Methods: We conducted a systematic review and modelling study and reviewed literature on the proportion of pregnant women who received pertussis-containing vaccines during pregnancy. Included articles were published before July 21, 2025 and identified through search of Web of Science, PubMed, Cochrane Library, Scopus, Embase, and Global Index. We also included relevant records from other official sources. With a purpose-built data collection form, information on study characteristics, sample characteristics, and MPV coverage levels were extracted from the studies. We developed a Bayesian model to fit and predict MPV coverage over time. Global, regional and national MPV coverages and numbers of pregnant individuals vaccinated during 2015-2023 among 15 countries with MPV policies were further generated. The study protocol was registered in PROSPERO, CRD42024543832. Findings: We included 936 country-year MPV coverage records from 15 high and upper-middle-income countries, compiled from 214 articles and data from WHO Joint Reporting Form (JRF), Pan American Health Organization (PAHO), and Government of the United Kingdom (GOV.UK). All 15 countries recommend tetanus, diphtheria, and acellular pertussis vaccine (Tdap), though vaccination timing varies significantly. Overall, global MPV coverage showed an inverted U-shaped trend, increasing from 2015 to 2019 [estimated annual percentage change (EAPC): 6.34, 95% uncertainty interval (UI): 5.18-7.52] and decreasing from 2020 to 2023 (EAPC: -1.15, 95% UI: -2.32 to 0.02). This decline was sharper in high-income countries. Some countries with high MPV coverage in 2019, particularly the United States of America (USA), Panama and Argentina, largely drove the global downturn from 2020 to 2023. For instance, USA MPV coverage dropped almost 13% from 2019 to 2023. Interpretation: MPV plays a key role for preventing pertussis, but MPV coverage needs to be improved, particularly in countries and territories where the pandemic may have had a long-term negative impact on MPV. Funding: This work was supported by National Social Science Foundation of China (Grant No. 22BGL246), Beijing Natural Science Foundation and Haidian Original Innovation (No. L222028), Joint Research Fund for Center for Infectious Diseases and Policy Research & Global Health and Infectious Diseases Group (Peking University) and Key Laboratory of Epidemiology of Major Diseases (Peking University), Ministry of Education.