Postpartum Ultrasound

This article describes uterine and uterine cavity changes throughout the normal and pathological puerperium, as revealed by various ultrasound modalities. A gray scale ultrasound, color and pulsed Doppler ultrasound and 3D ultrasound were used. It is based on results of several prospective longitudinal studies, which were designed so that every woman was examined at six occasions during the puerperium, namely on postpartum days 1, 3, 7, 14, 28 and 56. The first four examinations were performed transabdominally and the last two transvaginally. The same design was used in all studies. The involution process of the uterus was assessed by measuring the anteroposterior diameter of the uterus and uterine cavity. Morphological findings were recorded. The influence on the involution process of parity, breastfeeding, maternal smoking and infant's birth weight were also evaluated. Besides conventional ultrasound, Doppler technology was used to study hemodynamic events occurring during the normal puerperium. The pulsatility (PI) and resistance (RI) indices in the uterine arteries were measured, and the presence or absence of early diastolic notches was recorded. A hypervascular area in myometrium was assessed by color and power Doppler. Normal involution process was also described by means of 3D ultrasound. The volume of the uterus and uterine cavity after normal vaginal delivery were measured using virtual organ computer-aided analysis (VOCAL) using six adjacent planes and a 30° rotation method. Reference values from uncomplicated puerperium were used when pathological conditions were studied. Results from these studies, which shed light on normal and pathological changes during the puerperium, are summarized in this chapter.