The aim was to explore the possibility to diagnose retained placental tissue and other placental complications with 3D ultrasound and to investigate the impact of previous caesarean section on placentation in forthcoming pregnancies. 3D ultrasound was used to measure the volumes of the uterine body and cavity in 50 women with uncomplicated deliveries throughout the postpartum period. These volumes were then used as reference, to diagnose retained placental tissue in 25 women with secondary postpartum haemorrhage. All but three of the 25 women had retained placental tissue confirmed at histopathology. The volume of the uterine cavity in women with retained placental tissue was larger than the reference in most cases, but even cavities with no retained placental tissue were enlarged (Studies I and II). Women with their first and second birth, recorded in the Swedish medical birth register, were studied in order to find an association between previous caesarean section and retained placenta. The risk of retained placenta with heavy bleeding (>1,000 mL) and normal bleeding (≤1,000 mL) was estimated for 19,459 women with first caesarean section delivery, using 239,150 women with first vaginal delivery as controls. There was an increased risk of retained placenta with heavy bleeding in women with previous caesarean section (adjusted OR 1.61; 95% CI 1.44-1.79). There was no increased risk of retained placenta with normal bleeding (Study III). Placental location, myometrial thickness and Vascularisation Index were recorded on 400 women previously delivered by caesarean section. The outcome was retained placenta and postpartum haemorrhage (≥1,000 mL). There was a trend towards increased risk of postpartum haemorrhage for women with anterior placentae. Women with placenta praevia had an increased risk of retained placenta and postpartum haemorrhage. Vascularisation Index and myometrial thickness did not associate (Study IV). In conclusion: 3D ultrasound can be used to measure the volume of the uterine body and cavity postpartum, but does not increase the diagnostic accuracy of retained placental tissue. Previous caesarean section increases the risk of retained placenta in subsequent pregnancy, and placenta praevia in women with previous caesarean section increases the risk for retained placenta and postpartum haemorrhage.

<p>This study was undertaken to investigate the involutional changes of the uterus and uterine cavity by ultrasound (US), gray-scale and Doppler, after normal delivery, and to compare with the corresponding findings from women with puerperal complications, particularly retained placental tissue (RPT). The overall design was exploratory and prospective, with the use of descriptive statistics for analysis. </p><p>Forty-two women with uncomplicated vaginal term delivery were examined on post-partum days 1, 3, 7, 14, 28 and 56. The AP diameters of the uterus and uterine cavity and morphological findings were recorded. The maximum AP diameters of the uterus and uterine cavity diminished from 92.0 mm on day 1 to 38.9 mm at day 56 and from 15.8 mm at day 1 to 4.0 mm at day 56, respectively. The uterus was most often empty in the early and late puerperium while a mixed echo pattern over the whole cavity was found during mid puerperium (I).</p><p>Seventy-nine women with secondary post partum hemorrhage (SPH) were examined on the day they presented with clinical symptoms. US revealed an echogenic mass in the uterine cavity in 17 of 18 patients treated surgically and histology confirmed placental tissue in 14 of these. Sixty-one patients with either an empty cavity or mixed echo pattern had an uneventful puerperal course after conservative treatment (II).</p><p>AP diameters and morphological findings for 55 women with endometritis, 28 after caesarean section and 20 after manual evacuation of the placenta overlapped extensively with normal references (III).</p><p>The physiological vascular involution studied in 45 women after normal delivery showed that PI and RI indices did not change significantly until day 28 postpartum. The presence of at least one uterine artery notch was found in 13.3% of the women at day 1 and in 90.6% at day 56 postpartum (IV).</p><p>PI and RI values were measured and compared with reference values in 20 women with clinical suspicion of RPT who were to undergo surgical evacuation. Mean resistance indices were below the 10th percentile for eight of these 20 women, but overlapping was considerable. Doppler US has limited value as a diagnostic tool for RPT. The absence of a hyper-vascular area in the myometrium does not exclude RPT but an echogenic mass in the cavity is a sign of RPT (V).</p>

This study was undertaken to investigate the involutional changes of the uterus and uterine cavity by ultrasound (US), gray-scale and Doppler, after normal delivery, and to compare with the corresponding findings from women with puerperal complications, particularly retained placental tissue (RPT). The overall design was exploratory and prospective, with the use of descriptive statistics for analysis. Forty-two women with uncomplicated vaginal term delivery were examined on post-partum days 1, 3, 7, 14, 28 and 56. The AP diameters of the uterus and uterine cavity and morphological findings were recorded. The maximum AP diameters of the uterus and uterine cavity diminished from 92.0 mm on day 1 to 38.9 mm at day 56 and from 15.8 mm at day 1 to 4.0 mm at day 56, respectively. The uterus was most often empty in the early and late puerperium while a mixed echo pattern over the whole cavity was found during mid puerperium (I). Seventy-nine women with secondary post partum hemorrhage (SPH) were examined on the day they presented with clinical symptoms. US revealed an echogenic mass in the uterine cavity in 17 of 18 patients treated surgically and histology confirmed placental tissue in 14 of these. Sixty-one patients with either an empty cavity or mixed echo pattern had an uneventful puerperal course after conservative treatment (II). AP diameters and morphological findings for 55 women with endometritis, 28 after caesarean section and 20 after manual evacuation of the placenta overlapped extensively with normal references (III). The physiological vascular involution studied in 45 women after normal delivery showed that PI and RI indices did not change significantly until day 28 postpartum. The presence of at least one uterine artery notch was found in 13.3% of the women at day 1 and in 90.6% at day 56 postpartum (IV). PI and RI values were measured and compared with reference values in 20 women with clinical suspicion of RPT who were to undergo surgical evacuation. Mean resistance indices were below the 10th percentile for eight of these 20 women, but overlapping was considerable. Doppler US has limited value as a diagnostic tool for RPT. The absence of a hyper-vascular area in the myometrium does not exclude RPT but an echogenic mass in the cavity is a sign of RPT (V).