Placenta accreta risk—antepartum score in predicting clinical outcomes of placenta accreta spectrum: A multicenter validation study

Abstract

Objective: To validate the use of placenta accreta risk-antepartum (PAR-A) score as a predictive tool of clinical outcomes of placenta accreta spectrum (PAS).Methods: This is a prospective study, conducted in six PAS specialized centers in six different countries. The study was conducted between October 1, 2020 and March 31, 2021. Women who were provisionally diagnosed with PAS during pregnancy were considered eligible. A machine-learning-based PAR-A score was calculated. Diagnostic performance of the PAR-A score was evaluated using a receiver operating characteristic curve, for perioperative massive blood loss and admission to intensive care unit (ClinicalTrials.gov identifier NCT04525001).Results: Of 97 eligible women, 86 were included. PAS-associated massive blood loss occurred in 10 patients (11.63%). Median PAR-A scores of massive blood loss in the current cohort were 8.9 (interquartile range 6.9-14.1). In predicting massive blood loss, the area under the curve of PAR-A scores was 0.85 (95% confidence interval [CI] 0.74-0.95), which was not significantly different from the original cohort (P = 0.2). PAR-A score prediction of intensive care unit admission was slightly higher compared with the original cohort (0.88, 95% CI 0.81-0.95; P = 0.06). Conclusion:PAR-A score is a novel scoring system of PAS outcomes, which showed external validity based on current data.

Association between Antenatal Vaginal Bleeding and Adverse Perinatal Outcomes in Placenta Accreta Spectrum

“…Patients with multiple bleeding episodes were significantly more likely to experience an adverse outcome, and this significance was present for all individual components of the composite with the exception of EBL ≥ 2 L. Yet, the overall blood loss is high across groups. While there were more emergent deliveries in the group who experienced repeat occurrences of antenatal vaginal bleeding, prior studies have not shown an association between emergent delivery and adverse maternal outcomes [26,27].…”

“…The Placenta Accreta Index (PAI) correlates patients' prior cesarean section history, as well as ultrasound markers to predict the likelihood of PAS as a potential proxy for risk of morbidity [28]. The Placenta Accreta Risk-Antepartum (PAR-A) and Placenta Accreta Risk-Peripartum (PAR-P) scores are machine-learning-based tools that use several patient demographics, medical histories, and imaging data to predict morbidity in patients with PAS [27]. While these tools can aid in perioperative risk assessment, they each have their limitations in terms of specificity and generalizability.…”

Serum exosomal microRNA pathway activation in placenta accreta spectrum: pathophysiology and detection

“… 12 , 13 , 14 Current characterization of PAS relies on the combination of historic risk factors (previous uterine surgery) and ultrasonography findings (placenta previa, lacunae, and hypervascularity among others). 15 , 16 This approach has led to a PAS detection rate varying from 50% to 80% depending on the center and clinical suspicion. Although objective PAS detection through the use of biomarkers would be ideal, this remains elusive at this time.…”