Pathways to preterm birth: Case definition and guidelines for data collection, analysis, and presentation of immunization safety data
While immunizations confer protection against specific subtypes of infections, it is important to determine whether these interventions contribute to adverse maternal or neonatal outcomes in pregnancy. In particular, understanding the risk/benefit of immunizations with respect to pathways resulting in preterm birth is of particular interest. Preterm birth results from a variety of pathways ranging from idiopathic to spontaneous etiologies. Because there is a diverse spectrum of possible causes of preterm birth, it is important to determine whether some of the pathways to preterm birth can be activated by interventions, including immunizations.