VP45.01: Cervical elastography strain ratio and strain pattern for the prediction of a successful induction of labour

Abstract

Virtual poster abstractsObjectives: To evaluate whether serial change in cervical length (CL) over time can be a predictor for massive postpartum bleeding in patients with placenta previa. Methods: This was a retrospective cohort study of patients with placenta previa between January 2014 and November 2019. All women were offered serial measurement of CL by transvaginal ultrasound at 19-23 weeks (CL1), 24-28 weeks (CL2), 29-31 weeks (CL3) and 32-34 weeks (CL4). We compared clinical characteristics, serial change in CL, and outcomes between the massive postpartum bleeding group (case group) and control group. The predictive value of change in CL for emergency CS was evaluated. Results: A total of 93 women were evaluated; 31 had emergency CS due to massive vaginal bleeding. CL tended to decrease with advancing gestational age in each group. Until 29-31 weeks, CL showed no significant differences between the two groups, but after that, CL in the postpartum bleeding group decreased abruptly, even though CL in the control group continued to gradually decrease. On multivariate analysis to determine risk factors, only anterior placenta and change in CL were significantly associated with massive postpartum bleeding. Conclusions: CL should be included in the assessment of a placenta previa given its relationship to intraoperative blood loss.