Sonographic longitudinal cervical length measurements in nulliparous women at term; prediction of spontaneous onset of labour

Introduction The aim of this study was to predict spontaneous onset of labour by serial transvaginal ultrasound in a homogenous population of nulliparous women at term. Methods One hundred sixty two nulliparous women with a singleton fetus in cephalic position were examined at weekly intervals from 36 weeks of gestation to delivery. Cervical length (CL) was measured by transvaginal ultrasound in supine and upright position. Results There was a significant decrease in CL in the last twelve days prior to delivery, however this decrease was small with a substantial variation between individuals. Women with a sponta…