The active immunization of pregnant women during pregnancy to protect them from disease and protect their neonate with passive antibodies is a biologic fact. Fortunately, many infectious diseases occur infrequently due to excellent pediatric vaccine programs. However, most adults and many physicians are unaware of the risks of not administering vaccines especially to pregnant women. Influenza vaccine (trivalent inactivated influenza vaccine) is recommended by (Advisory Committee on Immunization Practices (ACIP) for pregnant women in any trimester of pregnancy and Tetanus, reduced diphtheria, and pertussis (TdaP) vaccine is recommended by the ACIP to be given before pregnancy, during pregnancy, or in the immediate postpartum period. Only 2% of the adult US population is protected against pertussis and it is estimated that only 25% of pregnant women receive influenza vaccine during the influenza season. This chapter discusses trivalent inactivated influenza vaccine and TdaP use during pregnancy, the diseases they prevent, and the benefit to the neonate.