A puzzling intrauterine death: non-compaction of the fetal ventricular myocardium presenting with reversed end-diastolic flow velocity in the umbilical arteries.

Background: Absent or reversed end-diastolic flow velocity (ARED) in the umbilical arteries is typically associated with severe intrauterine growth restriction (IUGR), although there may be other causes, such as aneuploidy.

Case: A healthy 30-year-old gravida 2, para 0 woman with an uneventful pregnancy and normal prenatal screening test results presented with sudden cessation of fetal movement at 26 weeks' gestation. Ultrasound demonstrated unexplained ARED with normal fetal growth and normal amniotic fluid volume. The fetus died during transfer to the labour and delivery unit. The cause of fetal demise was initially assumed to be feto-maternal hemorrhage, but postmortem examination revealed non-compaction of the ventricular myocardium.

Conclusion: Intrinsic myocardial disease should be considered in the differential diagnosis when ARED is discovered in the umbilical arteries, especially when fetal growth is normal. Postmortem examination should be performed even if a prior 18- to 20-week anatomical ultrasound has been reported as normal.