Mid-pregnancy cervical length in nulliparous women and its association with post-term delivery and intrapartum caesarean delivery

Mid-pregnancy cervical length in nulliparous women and its association with post-term delivery and intrapartum caesarean delivery Abstract Objective: To evaluate the association between mid-pregnancy cervical length and post-term delivery and caesarean delivery during labour. Study Design: In a multicentre cohort study, cervical length was measured in low-risk singleton pregnancies between 16 and 22 weeks of gestation. From this cohort we identified nulliparous women who delivered beyond 34 weeks and calculated cervical length quartiles. We performed logistic regression to compare the risk of post-term delivery and intrapartum caesarean delivery to cervical length quartiles, using the lowest quartile as a reference. We adjusted for induction of labour, maternal age, ethnicity, cephalic position, pre-existing hypertension and gestational age at delivery.