Diagnostic accuracy of ultrasound in detecting the depth of invasion in women at risk of abnormally invasive placenta: A prospective longitudinal study

Introduction: The aim of this study was to assess the diagnostic accuracy of ultrasound in detecting the depth of abnormally invasive placenta in women at risk. Material and methods: Prospective longitudinal study including women with placenta previa and at least one prior cesarean delivery or uterine surgery. Depth of abnormally invasive placenta was defined as the degree of trophoblastic invasion through the myometrium and was assessed with histopathological analysis. The ultrasound signs explored were: loss of clear zone, placental lacunae, bladder wall interruption, uterovesical hypervascularity, and increased vascularity in the parametrial region. Results: In all, 210 women were included in the analysis. When using at least one sign, ultrasound had an overall sensitivity of 100% (95% CI 96.5-100) and overall specificity of 61.9 (95% CI 51.9-71.2) for all types of abnormally invasive placenta. Using two ultrasound signs increased the diagnostic accuracy in terms of specificity (100%, 95% CI 96.5-100) but did not affect sensitivity. When stratifying the analysis according to the depth of placental invasion, using at least one sign had a sensitivity of 100% (95% CI 93.7-100) and 100% (95% CI 92.6-100) for placenta accreta/increta and percreta, respectively. Using three ultrasound signs improved the detection rate for placenta percreta with a sensitivity of 100% (95% CI 92.6-100) and a specificity of 77.2% (95% CI 69.9-83.4). Conclusion: Ultrasound has a high diagnostic accuracy in detecting the depth of placental invasion when applied to a population with specific risk factors for anomalies such as placenta previa and prior cesarean delivery or uterine surgery

Management of placenta accreta spectrum in low- and middle-income countries

Placenta accreta spectrum (PAS) can be associated massive intra- and post-operative hemorrhage which when not controlled can lead to maternal death. Important advances have occurred in understanding the pathophysiology and therapeutic options for this condition. The prevalence of PAS at birth is direct association with the cesarean delivery (CD) rate in the corresponding population and is increasing worldwide. Limited health infrastructure in low- and middle-income countries increases the morbidity and mortality of patients with PAS at birth. In many cases, obstetricians working in limited resources settings cannot follow some of the international guideline's recommendations and have to opt for low-cost management procedures. In this review, we describe the particularities of managing PAS care in low- and middle-income countries from of prenatal evaluation of patients at risk of PAS at birth, therapeutic options, and inter-institutional collaboration. We also propose a management protocol based on training of the local obstetric teams rather than on sophisticated technological resources that are almost never available in low-resource scenarios

Abnormal vascular architecture at the placental-maternal interface in placenta increta

Objective The objective of the study was to characterize the vascular architecture at the placental-maternal interface in pregnancies complicated by placenta increta and normal pregnancies. Study Design Vessel numbers and cross-section area density and spatial and area distributions in 13 placenta-increta placental beds were compared with 9 normal placental beds using computer-assisted image analysis of whole-slide CD31 immunolabeled sections. Results The total areas occupied by vessels in normal and placenta-increta placental beds were comparable, but vessels were significantly sparser and larger in the latter. Moreover, placenta-increta–vessel distributions (area and distance from the placental–myometrial junction) were more heterogeneous. Conclusion Size and spatial organization of the placenta-increta vascular architecture at the placental-maternal interface differed from normal and might partially explain the severe hemorrhage observed during placenta-increta deliveries