Challenges in vaccinating infants born to mothers taking immunoglobulin biologicals during pregnancy

While immunoglobulin biologicals are increasingly used during pregnancy, there have been concerns on the immune function and vaccination of infants born to mothers taking immunoglobulin biologicals. In addition to the detection of biologicals in cord blood, cases of severe neonatal neutropenia and fatal dissemination of Bacillus Calmette-Guérin (BCG) have been reported. With increasing number of infants exposed to immunoglobulin biologicals in utero, there is a need to address the challenges in vaccinating these infants. This review summarizes the available evidence to discuss the issues of immunoglobulin biological exposure in utero, neonatal immune function, long-term immune development, and the challenges and strategies of vaccinating newborns and infants who were born to mothers taking biologicals during pregnancy.