The significance of yellow vernix in the newborn.

Yellow staining of the vernix caseosa of the newborn baby is not uncommon. It occurs sometimes in cases of haemolytic disease due to Rh incompatibility and is a sign of a severely affected infant (Wallerstein, 1948). Otherwise, little attention has been paid to this clinical finding. Clifford (1948) stated that yellow staining of the vernix was observed in about 6 per 1,000 births in the Boston Lying-in Hospital. Of the babies with yellow vernix, 20% had the icterus gravis type of haemolytic disease with a mortality rate of 36% and the remaining 80% of the group had a mortality rate of 6 %. He believes that the yellow vernix in the latter group indicates that severe foetal anoxia, probably due to placental disease, has occurred, days or weeks, before delivery. Smith (1951) suggested that the condition was due to inadequate placental function. The present investigation was carried out in the Simpson Maternity Pavilion, Royal Infirmary, Edinburgh, to determine what factors, other than haemolytic jaundice, cause yellow vernix, and how commonly a poor neonatal prognosis is associated with it. The Investigation