Results of Fetal Ultrasound Imaging and Doppler Ultrasound Study Depending on the Factors of Perinatal Risk in Preterm Birth

Premature birth (PB) is associated with placental insufficiency, which is confirmed in the morphological study of the placenta. Ultrasonic markers of placental abnormalities, often preceding PB, have been identified: changes in placental structure, premature ripening of the placenta, oligohydramnios, and fetal-placental circulation.