Causes of Fetal Death: Comparison of Diagnostic Accuracy Between Extensive and Selective Protocol Testing

Intrauterine fetal death (IUFD) is defined as the occurrence of fetal death at >20 weeks' gestation. IUFD affects about 1 in 160 pregnancies (6-7 per 1000 births). Optimal diagnostic evaluation for cases of IUFD is generally based on extensive protocol testing i.e. maternal and fetal blood tests, fetal bacteriology, cytogenetic analysis, autopsy, and placental examination. This extensive protocol testing may vary in clinical practice and interpretation of the results is rarely performed by multidisciplinary staff to establish cause of death. These findings are related to the fact that there are very few epidemiological studies to validate optimal protocol, no French recommendations on this subject, and a relative lack of pathologists with expertise in perinatal pathology. Only, one recent prospective study from the Netherlands has concluded that extensive protocol testing should be redefined and some diagnostics tests may only be performed with suggestive clinical circumstances. However these recommendations may not be applicable to all populations and countries. To date, there are no French published series on IUFD to evaluate causes of death in France and thereafter to better define optimal diagnostic evaluation tests. Improvement in prenatal diagnosis in France may contribute to detection of the vast majority of severe chromosomal abnormalities and malformed fetuses and particularly those at risk of death. Retrospective cohort unpublished data on IUFD from Lille and Caen have reported exceptional deaths attributable to chromosomal or malformation abnormalities. In fact in these two series, most deaths were related to placental diseases or fetal growth retardation. The hypothesis is that extensive protocol testing is not helpful in clinical practice and selective protocol testing focused on specific risk situations can be as efficient.