• stillbirth investigation;
  • intrauterine fetal demise;
  • cause of death;
  • classification systems


Stillbirth accounts for about 26,000 deaths annually in the US. In most previous studies, discrete causes are identified in less than half of all stillbirths. In order to identify causes and non-causal but potentially contributing abnormalities, we analyzed 416 of the most recent (2004–2010) Wisconsin Stillbirth Service Program (WiSSP) cases from a multifocal approach. In 70% of cases a cause sufficient to independently explain the demise was identified including 40% placental, 21.5% fetal, and 12.7% maternal. Results for stillbirths and second trimester miscarriages did not differ significantly. In 95% of cases at least one cause or non-causal abnormality was recognizable, and in two-thirds of cases, more than one cause or non-causal abnormality was identified. In cases with maternal cause, the placenta was virtually always abnormal. Both placentas (59%) and fetuses (38%) were frequently smaller than expected for gestational age. Previous miscarriage and/or stillbirth were risk factors for second and third trimester losses, with 35% of previous pregnancies ending in fetal demise. Recommendations include complete evaluation of all second and third trimester losses with special attention to placental pathology and thorough investigation for multiple causes or abnormalities whether or not a primary cause is initially recognized. Improved understanding of the causes of late miscarriage and stillbirth may contribute to recognition and management of pregnancies at risk and eventually to prevention of stillbirth. © 2011 Wiley-Liss, Inc.