BACKGROUND: Maternal vaccination is key to decreasing maternal and infant mortality globally. Yet perceptions about maternal vaccines and immunization among pregnant women are often understudied, particularly in low- and middle- income countries. This qualitative study explored trust, views, and attitudes towards maternal immunization among pregnant women in Mexico. A total of 54 women from Mexico City and Toluca participated in the in-depth interviews and focus groups. We explored participants' experiences with maternal vaccination, as well as how they navigated the health system, searched for information, and made decisions around maternal immunization. RESULTS: Our findings point to issues around access and quality of maternal healthcare, including immunizations services. While healthcare professionals were recognized for their expertise, participants reported not receiving enough information to make informed decisions and used online search engines and digital media to obtain more information about maternal healthcare. Some participants held strong doubts over the benefits of vaccination and were hesitant about the safety and efficacy of maternal vaccines. These concerns were also shared by pregnant women who had been vaccinated. Some participants disclosed low levels of trust in government and vaccination campaigns. CONCLUSION: Pregnant women, soon to be parents and making vaccination decisions for their child, constitute an important target group for policymakers seeking optimal maternal as well as childhood immunization coverage. Our findings highlight the importance of targeted communication, trust-building and engagement strategies to strengthen confidence in immunization amongst this group.