Histopathological Changes of Placenta in Meconium Stained Liquor and Its Relevance in Fetal Distress: A Case Control Study

Abstract

Objective: Meconium passage during labour is a quite common finding. Studies describing correlation between meconium stained liquor, fetal distress and specific placental pathology are sparse. This case control study had been designed to ascertain these lacunae of knowledge. Material and Method:Placentae from 41 cases of otherwise uncomplicated antenatal and intranatal pregnancies with meconium stained liquor at 37 completed weeks of gestation were studied, both grossly and microscopically, comparing them with controls of 41 cases of clear liquor. Apgar score of all newborns at 1 minute and 5 minutes were recorded and correlated with histopathological findings. Results: Both cases and controls were found to be age matched. Meconium stained liquor was associated with more caesarian section than the clear ones. Significant correlation was found with meconium stained liquor and low Apgar scores. Histopathology of placenta revealed many statistically significant associations between specific placental histopathology in meconium stained liquor and depressed Apgar score. Evidence of placental vasculopathy rather than meconium induced placental damage came out as the potential culprit in causing a low Apgar score in this case control study. Conclusion: Placental vascular changes have a role in meconium staining of liquor. If timely interventions are taken, the chance of development of fetal distress is low.

Keywords

• Placenta
• Histopathology
• Meconium stained liquor
• Apgar score