a With adjustment for age at childbirth, year of childbirth, urbanization, severity of cervical disease (normal, CIN1, CIN2, or ≥CIN3), ethnicity, diabetes mellitus, maternal infection, epilepsy, psychiatric diseases, history of abortion, history of preterm birth, pregnancy by IVF, nulliparous women, pre-eclampsia, gestational diabetes, placental abruption, placenta or vasa previa, congenital diseases, intrauterine growth restriction, macrosomia, stillbirth, and fetal distress. b Women with induction of labor were excluded from analysis. c To adjust for multiple testing, we considered a P value of <0.01 statistically significant. d To prevent revealing data, numbers of less than 5 are grouped together, conform the rules of CBS. *Statistically significant. CBS, Statistics Netherlands; CI, confidence interval; CIN, cervical intraepithelial neoplasia; IVF, in vitro fertilization; NA, not applicable. (DOCX)