Serial cervical length measurements after the 1st episode of threatened preterm labor improve prediction of spontaneous delivery prior to 37 weeks' gestation

To assess whether repeated cervical length measurements in women discharged from the hospital after their first episode of threatened preterm labor can predict their risk of spontaneous preterm birth METHODS: This is a secondary analysis of a randomized controlled trial on maintenance tocolysis, in which cervical length was measured transvaginally at the time of hospital discharge and respectively after 2, 4, 8 and 12 weeks among women who remained undelivered after their first episode of threatened preterm labor. After univariate analysis, multivariate logistic regression was used to assess if cervical length < 10 mm at the time of hospital discharge or at any follow up evaluation could predict delivery prior to 37 weeks.