Then, to assess the roles of ASK1 in preterm birth, we used a preterm-birth mouse model induced by transvaginal injection of LPS into the cervix21, which mimics the pathological condition of chorioamnionitis resulting from bacterial infection ascending from the vagina up to the uterus, in wild-type mice and ASK1−/− pregnant mice. Here, MAP3K5 is linked to bacterial infectious disease.