IL1B and chorioamnionitis: Our results demonstrated the key role of IL-1 in driving GBS-induced chorioamnionitis through (i) upregulating pro-inflammatory cytokines and chemokines, (ii) increasing PMN infiltration in the decidua and labyrinth, (iii) inducing a FIRS within the labyrinth as well as downstream within the fetal sera, and (v) reducing neurobehavioral impairments in male and female offspring.