Fig. 4

Receiver operating characteristic (ROC) curves for myometrium thickness grades (a), dark intraplacental bands volume (b) to predict the risk of massive postpartum haemorrhage (Estimated blood loss volume ≥ 1000 ml). ROC curves for myometrium thickness grades (c), dark intraplacental bands volume (d) to predict the risk of severe postpartum haemorrhage (estimated blood loss volume ≥ 2000 ml)