Correlation of meconium-stained amniotic fluid, early intrapartum fetal pH, and Apgar scores as predictors of perinatal outcome.

Abstract

A prospective study was undertaken to determine if the passage of meconium during the early intrapartum period (cervical dilatation 3 cm or less), the type of meconium passed (thick versus thin), and fetal pH values could be correlated with Apgar scores as a predictor of neonatal outcome. One hundred seventy-seven patients had meconium-stained amniotic fluid and a cervical dilatation of 3 cm or less at admission. Group 2 (thick meconium) had significantly lower 1- and 5-minute Apgar scores, lower scalp pH values, and increased risk factors, such as prolonged pregnancy, small-for-gestational-age fetus, and fetal heart rate abnormalities. Group 2 (thin meconium) and the control group (nonmeconium) appeared to have no increased associated risks. Thick meconium as a single variable appeared to be the most significant factor influencing fetal outcome; however, if an associated fetal heart rate abnormality was present, perinatal morbidity was greatly increased as indicated by fetal acidosis and lower 1- and 5-minute Apgar scores. It thus appears that early passage of thick meconium does correlate with fetal outcome and increased perinatal morbidity. The significance of meconium passage is discussed and a modern obstetric management scheme for these high-risk patients is presented.