Correlation of Suspicious And Pathological Cardiotocography (CTG) with Umbilical Cord Blood Gas Parameters: A Prospective Cohort Study

Introduction -Fetal blood sampling is considered the best option in overcoming the increased false positivity of CTG but is not used in many developing countries due to logistics difficulties. Hence, obstetricians highly rely on CTG for diagnosing fetal hypoxia. Studies of suspicious and pathological CTG correlating with umbilical blood parameters are limited. Lactate can be a reliable marker to assess intrapartum hypoxia. However, the correlation of suspicious and pathological CTG with lactate is least studied. Methodology- A prospective observational cohort study was conducted to correlate suspicious and pathological CTG with umbilical cord arterial blood gas parameters in induced or laboring pregnant women and to compare the maternal and neonatal outcomes. Results - Out of 2350 women subjected to continuous CTG, 104 and 101 participants had suspicious and pathological CTG, respectively. A statistically significant association of CTG was seen in women with preterm delivery and with the use of tramadol. The association of primary outcomes like pH, base excess, and lactate with CTG findings was significant. Discussion - Other modalities to confirm acidosis should be used before an intervention in women with suspicious CTG. Drugs like tramadol and agents used for induction may play a role in abnormal CTG tracing in suspicious CTG. Cord blood lactate has a stronger association with CTG when compared with other umbilical cord parameters. Conclusion- Pathological CTG should be taken cautiously as it carries a greater risk of perinatal distress, but suspicious CTG tracing needs to be supplemented with additional tests before any interventions.