3D PDU is a recent development of ultrasound technology which allows the 3D reconstruction of vessels after their visualization using power Doppler ultrasound. It can be used for the assessment of vascularization and blood flow changes in relation to GA, visualization of fetal heart & great vessels, diagnosis of fetal vascular anomalies, ectopic pregnancy in a cesarean section scar and prenatal diagnosis of conjoined twins and Vasa previa.