P13.04: The role of ultrasound in prediction of successful induction of labour

Abstract

The aim of this study was to evaluate the potential value of cervical length and posterior cervical angle measurement by transvaginal ultrasound and determination of the fetal head position by transabdominal ultrasound before induction of labour in prediction of successful induction of labour. In a prospective study of 298 singleton pregnancies who admitted for induction of labour, after informed consent maternal characteristics were recorded. Fetal head position assessed by TAS, cervical length and posterior cervical angle measured by TVS. We examined the value of pre induction ultrasound parameters in prediction of labour induction outcomes. The cervical length measured by TVS was significantly shorter in patients who delivered vaginally in comparison with patients who delivered by Caesarean section due to the failure to progress.(18±5.7) versus (29.5±11) mm, respectively (p〈0.001). The odds ratio for successful induction for occiput anterior was 1.75(CI 95%=1.064-2.878) and for OP was 0.455 ,(CI 95%=0.272-0.763). And risk ratio for OA was 1.243(1.033-1.4950); and for OP was0.701 (CI 95%=0.541-0.908). The mean of posterior cervical angle in patients delivered vaginally was 124±18; and in patients with failed induction was 100±20.5 (P〈0.001). Using pre-induction ultrasound to determine fetal head position and cervical changes provides more precise information in comparison with Bishop score to predict the outcome of induction of labour, and enable clinicians to improve further management of pregnancy.