Elevated umbilical cord arterial lactate at birth and electronic fetal monitoring characteristics on admission and in the active phase

OBJECTIVE: To investigate the association between elevated umbilical arterial lactate at birth and electronic fetal monitoring (EFM) characteristics at admission and in the beginning of the active phase of labor. STUDY DESIGN: Nested case-control study within a prospective cohort of laboring patients at term who achieved active labor. Neonates with umbilical arterial lactate ≥ 4 mmol/L (cases, n=119), were matched 1:1 to controls with lactate <4mmol/L. EFM patterns were compared with multivariable logistic regression. RESULT: There were no differences in EFM parameters in the first 60 minutes after admission. At the beginning of active labor, 13.5% of cases and 26.1% of controls had always category I tracings, adjusted odds ratio 0.48, 95% confidence interval 0.24-0.94). Cases were less likely to have an always category I tracing from admission into the active phase. CONCLUSION: Elevated umbilical arterial lactate at birth is associated with distinct EFM patterns early in the labor course.