Electronic fetal monitoring: facts vs. myths
In light of the ongoing discussion in the comments section about electronic fetal monitoring, it seems worthwhile to review the current state of scientific evidence. A recent comprehensive treatment of issues in fetal monitoring, Medical Legal Issues in Fetal Monitoring (Clin Perinatol 34 (2007) 329–343), seems especially relevant because it addresses the way in which controversies in fetal monitoring are handled within the court system. The review lays out the issues:
... [EFMs] virtues are disparaged in various "evidence-based" articles that suggest that auscultation is comparable to EFM, or that EFM needlessly increases the operative delivery rate, but offers no benefit in prevention of neurologic injury or perinatal mortality...
...Pertinently, these articles and editorials do not call for the abandonment of EFM.
...Notwithstanding these developments, many lawsuits still involve allegations (and rebuttals) that the obstetrician either failed to recognize or act upon abnormal FHR patterns and that failure resulted in perinatal brain injury that could have been prevented.
The authors, Cohen and Shifrin, widely acknowledged to be experts in EFM, favor EFM over routine auscultation for the following reasons:
[We] resort to EFM as the primary screening test for intrapartum fetal asphyxia because of the limited predictive value of any other clinical risk factors during labor-including auscultation... EFM permits continuous accurate monitoring, permits using the fetus as its own control, evaluates tolerance of a fetus to stress of the individual uterine contraction, and permits the diagnosis of potentially catastrophic events in a timely fashion... There is no example of hypoxia or death on a monitor without warning. It provides a permanent record, subject to later review. With regard to auscultation, there is no study that supports the contention that auscultation is a reliable determinant of the fetal condition or of the need to intervene. Even those who find EFM useless for the purpose of preventing injury or death concede its ability to detect fetal hypoxia.
The authors conclude with an excellent summary of the current role of EFM in obstetrics and in obstetric malpractice suits:
Despite the persisting debates over its role and benefits, it is likely that EFM will remain a standard part of obstetric care for the foreseeable future. As such, it will also remain a focus of attention in obstetric negligence lawsuits. It must be remembered that in most cases the monitor pattern does not dictate the timing of intervention, but rather is used to keep mother and fetus out of harm’s way...
There is widespread agreement that improvement in perinatal outcome is possible, that the events of labor can contribute significantly to perinatal hazards, and that reviewing adverse outcomes and making obstetric units more reliable in terms of communication and interpretation of tracings will enhance outcome. (my emphasis) That notwithstanding, we do not yet know the totality of injury related to the intrapartum period irrespective of the mechanism. The estimates of the role of hypoxia vary widely, in great measure due to incompatible definitions and limited follow-up... In this respect, newer developments in pediatric neuroradiology and to some extent a more insightful approach to EFM may indeed help us understand these matters and at the same time improve outcome. It seems that we best protect ourselves in medicolegal matters when we protect the mother and the fetus during labor.
The bottom line is this: Neither doctors nor malpractice lawyers believe that the scientific evidence shows that intermittent auscultation is as effective as EFM, and that, therefore, the standard of care is the use of EFM. Essentially the only people who believe that the totality of the scientific evidence favors intermittent auscultation are "natural" childbirth and homebirth advocates.