An In-Depth Analysis and Classification of Placental Causes of Stillbirth: A 10-Year Retrospective Study of a Regional Stillbirth Registry

Introduction: Abnormal placental lesions are commonly identified in stillbirth. Interpreting these lesions and their contribution to fetal demise presents significant challenges. Recommended CODAC classification does not include detailed placental examination results. Objective: This study reports abnormal placental patterns in relation to the distribution of stillbirth causes in order to refine the categories of causes. Design: Data from the Ille-Et-Vilaine Stillbirth cohort, an exhaustive register of stillbirth cases across the Ille-et-Vilaine French department, were implemented in 2010. Setting: All seven maternity wards in the Ille-et-Vilaine department, France. Population: All cases of stillbirth located in the Ille-et-Vilaine department between 2010 and 2019. Methods: Descriptive statistics were used with the chi-squared test. Main Outcome Measures: All placental examinations were reported following the Amsterdam consensus. Cause of death was ascertained according to the CODAC (Classification of Cause of Death and Associated Conditions) classification during multidisciplinary meetings. Results: A total of 566 stillbirths were documented. The most frequent stillbirth causes were placental cause (36%), followed by umbilical cord (11%) and infections (9%). Stillbirth remained unexplained in 17% of cases. Small placenta and maternal malperfusion emerged as the most frequent placental lesions within the placental stillbirth group (65%), but also within the maternal cause groups (65%). Conclusion: Placental vascular anomalies were the most frequent cause of stillbirth in this study. Based on the combined use of international classification and observation of histological anomalies, our data suggest the existence of a vascular stillbirth group defined by vascular lesions associated with maternal or fetal expression.