The Stillbirth Classification System for the Safe Passage Study.
Objective Describe the classification system for assigning the cause of stillbirth in the Safe Passage Study, an international, multi-institutional, prospective analysis conducted by the NIAAA/NICHD-funded Prenatal Alcohol in SIDS and Stillbirth (PASS) Research Network. The study mission is to determine the role of prenatal alcohol and/or cigarette smoke exposure in adverse pregnancy outcomes, including stillbirth, in a high-risk cohort of 12,000 maternal/fetal dyads. Methods The PASS Network classification system is based upon 5 "sites of origin" for cause of stillbirth, further subdivided into mechanism subcategories; both are employed to assign an ultimate cause of death. Each PASS stillbirth was assigned a cause of death and status of sporadic versus recurrent. Adjudication involved review of maternal and obstetrical records; fetal autopsy and placental findings; and required complete consensus in each case. Two published classification systems, ie, INCODE and ReCoDe, were used for comparison. Results Causes of stillbirth classified were fetal (26%), placental (53%), external (5%), and undetermined (16%). Nine cases (47%) had placental causes of death due to maternal disorders that carry recurrence risks. There was full agreement for cause of death across the 3 classification systems in 26% of cases and partial agreement among them in 42% of cases. Conclusions The proposed PASS schema employs a user-friendly classification that provides comparable information to previously published systems. Advantages include its simplicity, mechanistic formulations, tight clinicopathologic integration, provision for an undetermined category, and its wide applicability to perinatal mortality review boards with access to information routinely collected during clinicopathologic evaluations.
1 Departments of Pathology, Boston Children's Hospital, Massachusetts, USA.|2 Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Theonia K
TK
Boyd
3 Department of Pathology, Faculty of Medicine and Health Science, Stellenbosch University, Western Cape, South Africa.|4 National Health Laboratory Services, Port Elizabeth, South Africa.
Colleen A
CA
Wright
5 Department of Obstetrics and Gynecology, Faculty of Medicine and Health Science, Stellenbosch University, Western Cape, South Africa.
Hein J
HJ
Odendaal
6 Center for Health Outcomes & Prevention, Sanford Research, Department of Pediatrics & Ob-Gyn, University of South Dakota Sanford School of Medicine, Sioux Falls, South Dakota, USA.
Amy J
AJ
Elliott
7 Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, North Dakota, USA.
Mary Ann
MA
Sens
1 Departments of Pathology, Boston Children's Hospital, Massachusetts, USA.|2 Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Rebecca D
RD
Folkerth
8 Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts, USA.
Drucilla J
DJ
Roberts
1 Departments of Pathology, Boston Children's Hospital, Massachusetts, USA.
Hannah C
HC
Kinney
9 The Prenatal Alcohol in SIDS and Stillbirth (PASS) Research Network.
D005260:Female; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D012107:Research Design; D012307:Risk Factors; D050497:Stillbirth
autopsy; human fetus; placenta; prenatal alcohol exposure; prenatal cigarette smoking exposure; undetermined stillbirth