Absent end diastolic flow in umbilical artery and umbilical cord thrombosis at term of pregnancy

Abstract

Background: Meconium staining of the fetus and placenta is associated with increased neonatal mortality and asphyxia. Very often it is unclear whether the discharge of meconium is a cause or an effect of fetal distress. In the available literature there are no large epidemiological studies of pregnancy outcome with meconium-related lesions, even though this could be useful to improve our state of knowledge on this topic.

Case report: A case of umbilical cord vascular necrosis is described. A severely asphyxiated infant was delivered at 39 weeks' gestation by cesarean section due to alarming results of fetal heart rate monitoring and rupture of membranes with meconium-stained amniotic fluid. There was no meconium aspiration. We report a review of 15 similar cases. In the whole series, a linkage between umbilical cord vascular necrosis and evidence of remote meconium discharge always seems to be detectable. The pathophysiological mechanism is unknown.

Conclusions: It is still not clear why only a tiny percentage of cases with meconium-stained amniotic fluid develops umbilical cord lesions and poor pregnancy outcome. Further investigations are needed to explain why some meconium-stained newborns suffer severe neurological and other damage even without meconium aspiration.