Association between total deceleration area, meconium-stained amniotic fluid and fetal distress among acidemic neonates

Abstract Purpose Total deceleration area (TDA) is a recognized indicator of intrapartum fetal acid–base status and correlates with neonatal morbidity. Meconium-stained amniotic fluid (MSAF) is similarly associated with neonatal acidosis and adverse outcomes. This study aimed to evaluate the relationship between TDA and MSAF among acidemic neonates. Methods We conducted a retrospective cohort study of singleton deliveries at a tertiary center (2014–2021) resulting in acidemic neonates (umbilical cord pH < 7.10). Maternal and obstetric characteristics, TDA, pH, and neonatal outcomes were compared between births with and without MSAF. TDA was calculated over the 60 min preceding delivery using electronic fetal monitoring (EFM) tracings, summing the area under each deceleration curve: heart rate change (bpm) × time (seconds)/2. Results Among 249 acidemic neonates, 55 had MSAF and 194 had clear fluid. Gestational age was higher in the MSAF group (40 vs. 39 weeks, p < 0.001), but labor characteristics and mode of delivery did not differ. TDA values were similar between groups ( p = 0.32) as were other EFM parameters (baseline, variability, tachycardia/bradycardia). However, neonates with MSAF had lower umbilical pH [median 7.03 (IQR 7.00–7.07) vs. 7.05 (7.01–7.08), p = 0.019], higher base deficit [median − 10.7 (− 12.2 to − 8.5) vs. − 9.3 (− 11.3 to − 7.7), p = 0.024], and with higher neonatal sepsis rates (7.3% vs. 1.5%, p = 0.04). Severe acidemia (cord pH < 6.9) was also significantly more common in the MSAF group (9.1% vs. 2.6%, p = 0.030). Multivariate analysis confirmed MSAF independently reduced pH by 0.027 units (95% CI − 0.052 to − 0.003) and increased base deficit by − 1.39 (95% CI − 2.60 to − 0.17). Conclusion MSAF is linked to greater fetal acidemia and neonatal compromise in cases where the TDA is similar. These findings indicate the need for increased caution and possibly quicker decision-making regarding delivery when MSAF and decelerations are present.