Prelabor short-term variability in fetal heart rate by computerized cardiotocogram and maternal fetal doppler indices for the prediction of labor outcomes

Abstract

Objectives

To investigate (i) the association between pre-labor maternal-fetal Dopplers and fetal heart rate short-term variability (FHR STV) with arterial cord blood pH and (ii) the potential value of pre-labor maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria in predicting composite neonatal morbidity at term in a cohort of unselected women.

Method

A prospective study in 218 women with term singleton pregnancy in latent phase of labor or due to undergo induction of labor. Data on maternal characteristics, maternal-fetal Dopplers indices and computerized cardiotocography (CTG) findings of FHR STV and Dawes-Redman criteria were collected. Pearson correlation analysis was used to determine the relationship between maternal-fetal Dopplers and FHR STV and arterial cord blood pH. Logistic regression analysis was used to determine which factors amongst maternal characteristics, labor onset, indication of labor induction, estimated fetal weight (EFW), maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria were significant predictors of composite neonatal morbidity and arterial cord blood pH less than 7.2.

Result

Of the 218 cases, 12 (5.5%) women were delivered by emergency operative delivery for pathological CTG, and 42 babies (19.3%) had composite neonatal morbidities. Arterial cord blood pH was not associated with maternal-fetal Doppler indices and FHR STV, but rather it was associated with maternal age and body mass index. The composite neonatal morbidity and arterial cord blood pH less than 7.2 were not significantly associated with maternal characteristics, labor onset, indication of labor induction, pre-labor assessment of EFW, maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria by computerized CTG.

Conclusion

In unselected women in latent phase of labor or undergoing induction of labor at term, admission maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria are not predictive of composite neonatal morbidity.

Keywords:

• Uterine artery pulsatility index
• umbilical artery pulsatility index
• middle cerebral artery pulsatility index
• computerized cardiotocography
• fetal heart rate short-term variability
• Dawes-Redman criteria

Acknowledgements

We would like to thank David Stange for the Sonicaid Team 3 Fetal Monitor CTG machine, with the Sonicaid Centrale Huntleigh software, provided by Tronda Electronics Ltd., Hong Kong. We would like to thank Angela S.T. Tai, Ching Man Mak, Tracy C.Y. Ma, Katrina M.H. Ng, Kimberley Zhang, Chit Ying Lai, Po Lan Iu in assisting with patient recruitment, and midwives and doctors at the Prince of Wales Hospital in facilitating the performance of this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).