268 Utility of the INCODE algorithm to identify cause of stillbirth in clinical settings

Abstract

The Initial Causes of Fetal Death Evaluation (INCODE) algorithm was developed by the Stillbirth Collaborative Research Network (SCRN) as a research tool to assign causes of death of stillbirth in which standardized postmortem examination (PME) is performed. Our goal was to assess the utility of INCODE in a retrospective cohort of stillbirths (SB) at a single tertiary hospital where PME was not routinely performed. Chart reviews were performed for all cases of SB from Dec 2013 to Oct 2019. Narrative summaries and PME results were recorded. Cause of death was assigned based on INCODE as described by SCRN investigators. Of the 99 identified SB, probable cause of death was identified in 70 (70.7%; 95% CI, 61.7-79.7%) and possible or probable cause in 92 (92.9%; 95% CI, 87.9-98.0%). The most common causes of SB were placental (n=40 [40.4%; 95% CI, 30.7-50.1%]), obstetric (n=36 [36.4%; 95% CI, 26.9-45.8%]), and fetal genetic/structural abnormalities (n=28 [28.3%; 95% CI, 19.4-37.2%]). Most frequently performed testing included maternal antibody screen (98; 99.0%), syphilis screening (91; 91.9%), and placental histology (94; 94.9%) while less than half of cases underwent PME (45; 45.5%). While antibody screen and syphilis testing infrequently yielded positive results (n=4, 4.1%; and 0), placental histologic examinations (n=72, 76.6%) and PME (n=36, 80%) contributed significantly to the assignment of possible or probable cause of death. Of women with SB and no PME (n=54), probable cause of SB was found in 61% (n=33 [95% CI, 48.1-74.1%]) and probable or possible cause identified in 89% (n=48 [95% CI, 80.5-97.3%]). Over one-third of SB occurred between 20 to 24 weeks gestation (n=38; 38.4%). Of SB at gestations less than 24 weeks, a greater proportion of SB occurred intrapartum than those at 24 weeks or later (34.1%vs12.7%; 95% CI, 4.8-37.9%, P=0.011). The INCODE algorithm identified a possible or probable cause of death in the majority of SB, comparing favorably to the results reported by SCRN, confirming its utility in a clinical setting where PME is not routinely performed.