Intrapartum fetal heart rate monitoring. III. Association of meconium with abnormal fetal heart rate patterns.

Fetal heart rate (FHR) tracings of 284 fetuses with meconium-stained amniotic fluid (MSAF) and 1,672 fetuses without meconium staining were compared to investigate the significance of meconium associated with normal and abnormal FHR patterns. MSAF was found to be associated with significantly more low 1- and 5-minute Apgar scores and higher neonatal mortality rates than the control group without meconium. An increase in abnormal FHR patterns in the MSAF group over the control group as well as the postpartum sequelae of meconium itself was likely responsible for the unfavorable outcome. It is concluded that the presence of meconium should be viewed as a warning sign of fetal distress which warrants close intrapartum observation of the patient.