Pregnant women's knowledge, perceptions, and intention to receive a future group B Streptococcus (GBS) vaccine: a cross-sectional study

BACKGROUND: Group B Streptococcus (GBS) is a major cause of neonatal morbidity and mortality. As maternal GBS vaccines progress toward licensure, understanding the determinants of acceptance is essential. This study assessed pregnant women's knowledge of GBS, perceptions of vaccine safety and effectiveness, and intention to receive a future maternal GBS vaccine in Greece. METHODS: A cross-sectional survey was conducted among pregnant women attending routine antenatal care at a tertiary hospital in Northwest Greece (July-November 2025). A structured, self-administered questionnaire assessed GBS knowledge, awareness of preventive measures, beliefs regarding vaccine safety and breastfeeding, prior maternal vaccination, and intention to receive a future GBS vaccine. Descriptive statistics, chi-square tests, and binary logistic regression were used to identify predictors of vaccine acceptance. RESULTS: A total of 421 women participated. General awareness of GBS was moderate (68.9%), while awareness of preventive measures, neonatal consequences, and prenatal testing was lower. Intention to accept a future GBS vaccine was evenly divided (49.9%). In multivariable analysis, higher educational level, awareness of preventive measures, pregnancy complications, and prior Tdap vaccination were associated with increased acceptance. Concerns about long-term adverse effects, perceived impact on breastfeeding, and conception via IVF were associated with reduced acceptance. CONCLUSIONS: Despite limited GBS awareness, nearly half of pregnant women expressed willingness to receive a future GBS vaccine. Acceptance was shaped by safety perceptions, breastfeeding concerns, and prior maternal vaccination. Strengthening communication, consistent provider messaging, and targeted support for specific subgroups may be important for the successful implementation of maternal GBS vaccination in Greece.