Cerebroplacental ratio thresholds measured within two weeks of birth and the risk of Cesarean section for intrapartum fetal compromise and adverse neonatal outcome

4 years ago

Cerebroplacental ratio thresholds measured within two weeks of birth and the risk of Cesarean section for intrapartum fetal compromise and adverse neonatal outcome

Sailesh Kumar, Amal A. Alsolai, Larissa N. Bligh, Ristan M. Greer

Objectives Prediction of intrapartum fetal compromise in uncomplicated, term pregnancies is a global obstetric challenge. Currently, no widely accepted screening test for this condition exists, although the cerebroplacental ratio (CPR) shows promise. We aimed to prospectively evaluate the screening performance of the CPR 10th centile for detection of Cesarean section for intrapartum fetal compromise (IFC) and composite adverse neonatal outcome (ANO) in low-risk women from 36 weeks and to determine the best CPR threshold from three previously described in the literature. Methods In a blinded, prospective, observational, cohort study, 483 women with uncomplicated singleton pregnancies underwent fortnightly CPR measurement from 36 weeks to delivery and intrapartum and neonatal outcomes were recorded. The CPR 10th centile threshold screening test performance was calculated for emergency Cesarean section for IFC and composite ANO, incorporating acidosis at birth, Apgar <7 at five minutes or admission to the neonatal intensive care unit. Screening performance evaluation of three previously reported CPR thresholds, CPR ≤1, CPR <5th centile and CPR <10th centile, was also undertaken for these specified outcomes. Results Four hundred and fifty eight women were included in the analysis, of which 4.1% had an emergency Cesarean section for IFC and 17.9% had a composite ANO. Sensitivity and specificity for CPR <10th centile were 55.6% and 87.9%, and 28.2% and 88.0%, for Cesarean section IFC and composite ANO, respectively. Comparing the three CPR thresholds, CPR <10th centile resulted in the best overall test performance (Cesarean section for IFC area under the receiver operating characteristic curve = 0.72, composite ANO area under the receiver operating characteristic curve = 0.58), although its predictive utility was only fair for Cesarean section for IFC and poor for composite ANO. Conclusion The CPR 10th centile may be useful as a component of a risk assessment tool for Cesarean section for IFC in low risk pregnancies at term.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/uog.17542