Association between Intrapartum Cardiotocography and Umbilical Cord Blood pH in Term Pregnancies: A Cross-sectional Study in a Tertiary Care Centre, Kolkata, India

Abstract

Introduction: Labour, a physiological process for majority of foetuses, often acts as a challenge to foetal reserves causing foetal hypoxia. Foetal monitoring with intrapartum cardiotocography is an important tool to enable timely intervention to reduce adverse neonatal outcomes like postnatal cerebral palsy. Aim: To determine an association between cardiotocography tracing and umbilical artery cord blood pH in term pregnancies in labour where the influence of drugs and the presence of other comorbid medical/obstetric adverse outcomes have been ruled out. Materials and Methods: This cross-sectional, hospital-based, observational study involved singleton uncomplicated term pregnancies with a normal baseline cardiotocography and spontaneous labour onset and progression admitted to the labour ward of R.G. Kar Medical College and Hospital, Kolkata, West Bengal, India. Intrapartum continuous cardiotocography traces were recorded and those showing abnormal traces were documented and delivery expedited within two hours. Total of 90 such consecutive women were included in the study and umbilical arterial cord blood sample was taken for all these pregnancies immediate postpartum. Cardiotocography traces were then statistically compared with cord blood parameters and the findings were computed using Statistical Package for the Social Sciences (SPSS) software version 22.0. Results: Out of 90 participants the mean age was 24.21±3.43 years, most (43, 47.8%) of them were in between 21 to 25 years. Of the abnormal traces, 51 (56.7%) were NICE Category II (Suspicious) and 39 (43.3%) were NICE category III (pathological). Cord blood analysis revealed that 40% had a pH<7, 44.4% had blood lactate levels above 6 mmol/L and another 47.7% had a base deficit ≥12 mmol/L. On crosstabulation and Chi-square analysis, these were all found to be statistically significant (p-value <0.05). Abnormalities of Foetal Heart Rate (FHR) and baseline variability had higher Odds ratio of predicting umbilical artery acidemia with Odd’s ratio for baseline variability abnormality as high as 2.768. Conclusion: Although there has been a rising trend towards operative deliveries, the overall incidence of neonatal morbidity due to cerebral palsy is still on the rise. Cardiotocography can be a very important tool to identify neonatal acidosis in “at risk” foetuses and helps in timely intervention giving long term best outcomes.

Cardiotocography use for fetal assessment during labor in low‐ and middle‐income countries: A scoping review

“…We then performed a full‐text review of 210 articles and excluded an additional 143. Finally, we included 67 studies in the study for extraction of data 12–79 …”

“…Table 1 provides the characteristics of the included studies. Our review identified eight intervention studies, including randomized controlled trials (RCTs) 12,13,18–20,23 and quasi‐experimental studies 17,22 ; and 59 observational studies, including cohort studies, 15,24–26,28–30,32,34,36–38,40,41,43,46,47,50,56–58,61,63,65–71,73–75,77,78 case–control studies, 27,33,35,39,42,44,45,48,49,52,53,55,62,64,72 before and after studies, 14,16,21,31 and cross‐sectional studies 51,54,60,76,79 . These studies were published between 1974 and 2023.…”

“…Table 1 provides the characteristics of the included studies. Our review identified eight intervention studies, including randomized controlled trials (RCTs) 12,13,[18][19][20]23 and quasi-experimental studies 17,22 ; and 59 observational studies, including cohort studies, 15,[24][25][26][28][29][30]32,34,[36][37][38]40,41,43,46,47,50,[56][57][58]61,63,[65][66][67][68][69][70][71][73][74][75]77,78 case-control studies, 27,33,35,39,42,44,…”

“…51,54,60,76,79 These studies were published between 1974 and 2023. Of the 67 studies included in the review, which were all conducted in lower-middle or upper-middle income countries, 28 (54%) were in India, 13,15,19,23,24,29,32,34,37,41,44,46,50,57,58,61,65,[67][68][69][71][72][73][74][75][76][77]79 followed by five (7%) each in China 28,33,53,55,66 and Pakistan, 22,35,40,54,60 and four (6%) each in South Africa 21,[25][26][27] and Iran. 18,47,49,…”