Clinical evaluation of the fetus and neonate. Relation between intra-partum cardiotocography, Apgar score, cord blood acid-base status and neonatal morbidity.

The relation between intra-partum cardiotocography (CTG), cord blood acid-base status, Apgar score and neonatal morbidity was studied in 1228 consecutively live-born babies and in a subgroup of 200 babies (148 babies with a 1 min Apgar score < or = 8 and 52 randomly selected babies with a 1 min Apgar score > or = 9). The scores for the individual components of the 1 min Apgar score were strongly associated with each other, whereas the scores for the individual components of the 5 min Apgar score were less strongly associated. At 1 min the scores for muscle tone, reflex irritability and respiration but not the scores for heart rate and skin colour were associated with arterial and venous cord blood pH (low scores being associated with low pH). Out of the individual components of the Apgar score, heart rate and reflex irritability at 1 min were the best discriminators between "healthy or relatively healthy" and "severely ill" babies. Intrapartum CTG, total Apgar score and cord blood acid-base status were only weakly related. Venous cord blood pH was the best predictor of the 1 min Apgar score. Intra-partum CTG (silent pattern), 5 min Apgar score and venous cord blood pH were the best predictors of severe neonatal morbidity.