In 2008, a pivotal study conducted in Bangladesh was published (14). This study demonstrated for the first time that maternal vaccination with influenza vaccine can protect mothers and their infants from laboratory confirmed influenza illness, with an efficacy in preventing infant influenza of 63%, similar to that achieved with active immunization. This study led to the support to three large studies of influenza vaccination of pregnant women by the Bill and Melinda Gates Foundation, conducted in Nepal, Mali, and South Africa. These seminal studies have now been completed, contributing significantly to the knowledge of the benefits and safety of influenza vaccination of mothers and infants, including HIV infected women, and providing critical information to guide decisions and policies surrounding maternal immunization (15–17). One important contribution of these trials was the determination of the relatively limited duration of protection of infants provided by maternally derived antibody, which decreased substantially after the second month of life (39). The 2009–2010 influenza pandemic was another critical event that resulted in the subsequent prioritization of maternal immunization research in the US and worldwide. The number of clinical trials and publications on the topic of maternal immunization has increased substantially since the pandemic. Importantly, the knowledge gained in aspects related to safety, immunogenicity, and implementation of influenza vaccines for pregnant women has resulted in more advances in this field than ever. An example of this was the acquisition of data on the safety and effectiveness of adjuvanted influenza vaccines in pregnant women (40). In general, there is a need for more immunogenic vaccines for use in all populations, including pregnant women, to improve effectiveness and further reduce the impact of influenza.