Meconium may normally be passed by term fetuses during labour. Common after 40 weeks and not a sign of fetal distress Before 40 weeks can implicate fetal distress If occurring in preterm fetuses or if present prior to labour, it may be considered a possible indication of fetal distress. Histopathology may estimate the duration of meconium passage. Macrophages containing meconium are present at the chorionic surface or deeper portions of the membrane and can be easily identified not only on routine hematoxylin-eosin staining but also with the help of immunohistochemistry.