Intrapartum category II cardiotocography and its association with mode of delivery and perinatal outcomes in term pregnancy: a prospective observational study
DOI:
https://doi.org/10.18203/2320-1770.ijrcog20262338Keywords:
Fetal heart rate monitoring, Caesarean section, Fetal monitoring, Labor, Obstetric, Neonatal morbidity, PregnancyAbstract
Background: Intrapartum cardiotocography (CTG) is widely used for foetal surveillance. However, Category II CTG has variable patterns and uncertain significance, often leading to operative delivery in pregnant women. This study aimed to assess the association between intrapartum Category II CTG, mode of delivery, and perinatal outcomes in term pregnancies.
Methods: This prospective observational study was conducted at the Department of Obstetrics and Gynaecology, Sri Ramakrishna Hospital, Coimbatore, between December 2019 and August 2020. A total of 103 consecutive term pregnant women with intrapartum Category II CTG were included. The mode of delivery and perinatal outcomes were analysed in relation to parity, modified Bishop score, CTG duration, and CTG pattern type.
Results: Among the study population, 55.3% underwent emergency caesarean section, while 44.7% delivered vaginally, including 31.1% by operative vaginal delivery and 13.6% by normal vaginal delivery. All women with unfavourable modified Bishop scores underwent emergency caesarean section (100%). With favourable Bishop scores, operative vaginal delivery was common in both primigravida (42.6%) and multigravida (40.9%) groups. The duration of category II CTG differed according to parity (p=0.041) but was not associated with neonatal outcomes. NICU admission occurred in 37.9% of neonates, most frequently with reduced variability (66.7%) and foetal tachycardia (55.6%) (p=0.027). Most NICU stays were less than 24 h (60.5%).
Conclusions: Intrapartum Category II CTG is associated with higher operative delivery rates; however, perinatal outcomes are generally favourable and depend more on CTG pattern type than on duration. Careful intrapartum reassessment may help reduce unnecessary caesarean sections.
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