NEJM: Uncertain Value of Electronic Fetal Monitoring in Predicting Cerebral Palsy

by faithgibson on May 25, 2016

Uncertain Value of Electronic Fetal Monitoring in Predicting Cerebral Palsy

Karin B. Nelson, M.D., James M. Dambrosia, Ph.D., Tricia Y. Ting, B.S., and Judith K. Grether, Ph.D.

N Engl J Med 1996; 334:613-619March 7, 1996

Electronic fetal monitoring during labor was developed to detect fetal-heart-rate patterns thought to indicate hypoxia. The early recognition of hypoxia would, it was reasoned, alert clinicians to potential problems and enable them to intervene quickly to prevent fetal death or irreversible brain injury.

When electronic fetal monitoring was introduced, it was hoped that the use of this technique would prevent the majority of birth injuries due to hypoxia or asphyxia, thus greatly reducing the frequency of cerebral palsy and mental retardation.

The introduction and wide dissemination of fetal monitoring occurred before randomized clinical trials had evaluated its efficacy. More than 20 years and 11 randomized trials later,1-6 electronic fetal monitoring appears to have little-documented benefit over intermittent auscultation with respect to perinatal mortality or long-term neurologic outcome.

Furthermore, probably in part because of the widespread use of fetal monitoring, [7] the rate of cesarean section has increased, with a resulting increase in maternal morbidity and costs but without apparent decrease in the incidence of cerebral palsy.

Few of the trials performed so far have been large enough or have lasted long enough to investigate a possible association between findings on fetal monitoring and a relatively rare outcome such as cerebral palsy, which can be confidently diagnosed only years after birth. No randomized trial has explored possible associations between specific heart-rate patterns detected on electronic monitoring and long-term neurologic outcomes.

In a population-based study, we assessed the association of cerebral palsy in children with birth weights of 2500 g or more with specific patterns on fetal monitoring and evaluated the possible confounding effects of other risk factors. We investigated the usefulness of fetal monitoring as interpreted by the treating physicians at the time of the delivery of infants who would later be given the diagnosis of cerebral palsy.