Association Between Intrapartum Cardiotocogram and Early Neonatal Outcomes in a Tertiary Hospital in Thailand.

Background: Intrapartum electronic fetal monitoring (EFM) has widely been used to monitor mothers in labor who are at risk in clinical practice. There is little evidence to describe the association between EFM categories based on the newly proposed National Institute of Child Health and Human Development (NICHD) 2008 criteria and neonatal outcomes.

Objective: To investigate the association between intrapartum cardiotocogram categories based on the NICHD 2008 and early neonatal outcomes

Material and Method: Intrapartum EFM tracings of 120 singleton pregnant women of equal or more than week gestation were evaluated according to NICHD 2008 guidelines. Neonatal outcomes included Apgar scores at 1 and 5 minutes, umbilical cord blood pH, and neonatal intensive care unit (NICU) admission. The association between EFM and neonatal outcomes was analyzed using logistic regression.

Results: Among the 120 mothers, 83 (69.2%) had EFM tracings classified as Category I and 37 (30.8%) as Category II. Compared to EFM Category I, Category II had a 5-fold higher risk of having 1-minute Apgar score of <9 (adjusted odds ratio (OR) 4.96, 95% CI 1.03 to 24.00, p = 0.046) and 38-folds higher risk of having neonatal acidosis (adjusted OR 37.88, 7.33 to 195.90, p<0.001). Variable deceleration was associated with a 6-fold increased risk of having 1-minute Apgar score of <9 (OR 6.26, 1.23 to 31.80, p = 0.027). The presence of minimal variability and variable deceleration increased the riskof having neonatal acidosis by 16 and 8 times (OR 15.89, 3.42 to 73.80, p<0.001 and 7.84, 1.45 to 42.48, p = 0.017, respectively).

Conclusion: EFM category II according to NICHD 2008 classification was associated with higher risk of having low Apgar score at 1 minute and neonatal acidosis than EFM category I.