Learning from Loss: Placental and Autopsy Insights: Abstract 12: Decoding Stillbirth: A 6-year Placental and Cord Pathology Study Using Amsterdam 2016 Classification

Abstract Background: Placental and umbilical cord pathology provide crucial insights into stillbirth causes. The Amsterdam Consensus 2016 standardizes classification of placental lesions, improving diagnostic consistency and clinical counselling. Aim: To analyze placental and cord findings in stillbirths, classify lesions using Amsterdam 2016 criteria, and assess the diagnostic yield across gestational age groups. Methods: A retrospective study of 89 stillbirths at Mediscan, Chennai (2018–2024) was conducted. Placental gross and microscopic findings and cord morphology were reviewed. Lesions were classified as maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM), villitis of unknown etiology (VUE), or chorioamnionitis. Gestational age was grouped as early (22–27 weeks 6 days), late (28–36 weeks 6 days), or term (≥37 weeks). Results: Of the 89 cases, 59% were early stillbirths (n=53), 35% late stillbirths (n=31), and 6% term stillbirths (n=5). MVM was the most frequent lesion (~40%), predominantly in early and late groups. FVM accounted for ~17%, often with cord anomalies. VUE and chorioamnionitis were less common (11% and 5%). Overall, 73% of cases had an identifiable placental or cord cause, while 27% remained unclassified. Conclusion: Systematic placental and cord examination using the Amsterdam 2016 criteria yielded a probable cause in nearly three-fourths of stillbirths, underlining its critical role in identifying preventable factors and counselling families. Complete autopsy and better sampling can help address remaining unexplained cases.