Abstract
Background: Fetal heart rate (FHR) monitoring during the second stage of labour is a central component of intrapartum surveillance, permitting early recognition of evolving fetal hypoxia and timely obstetric intervention. Abnormal FHR patterns have been associated with adverse neonatal outcomes including low Apgar scores, birth asphyxia and admission to the neonatal intensive care unit (NICU).
Objective: To evaluate the association between fetal heart rate patterns during the second stage of labour and neonatal outcomes at a rural tertiary care teaching hospital.
Methods: This prospective observational study was conducted in the Department of Obstetrics and Gynaecology over an 18-month period. Two hundred women with term singleton cephalic pregnancies entering the second stage of labour were enrolled consecutively. Continuous cardiotocography was interpreted according to the FIGO 2021 intrapartum classification as normal, suspicious or pathological. Maternal characteristics, intrapartum events, mode of delivery and neonatal outcomes were recorded, with neonatal assessment performed by a paediatrician blinded to the cardiotocographic findings. Categorical associations were tested by the chi-square or Fisher’s exact test and continuous variables by Student’s t-test or the Mann–Whitney U test, with p < 0.05 considered significant.
Results: Fetal heart rate patterns were normal in 128 women (64.0%), suspicious in 44 (22.0%) and pathological in 28 (14.0%). Variable decelerations were the commonest abnormality (13.0%), followed by late decelerations (9.0%) and reduced baseline variability (5.5%). Emergency caesarean section was performed in 57.1% of women with pathological tracings compared with 9.4% of those with normal tracings (χ² = 32.84, p < 0.001). Neonates delivered after pathological tracings had significantly higher rates of Apgar < 7 at one minute (53.6% vs 6.3%), neonatal resuscitation (57.1% vs 7.0%) and NICU admission (50.0% vs 4.7%) (all p < 0.001). Late decelerations carried the highest crude odds of adverse neonatal outcome (OR 8.9), followed by prolonged decelerations (7.4) and reduced variability (6.8). Overall, 170 neonates (85.0%) were healthy at birth; birth asphyxia occurred in 25 (12.5%), hypoxic-ischaemic encephalopathy in 2 (1.0%) and early neonatal death in 3 (1.5%).
Conclusion: Pathological fetal heart rate patterns during the second stage of labour were strongly associated with operative delivery and adverse neonatal outcome, with late decelerations and reduced baseline variability the most informative individual abnormalities. Continuous electronic fetal monitoring with systematic interpretation and prompt intervention supports early recognition of fetal compromise. These associations are unadjusted and should be interpreted as hypothesis-generating pending multivariable analysis.