On one hand, the well-conducted prospective study by Weiner et al could be considered a very good-quality evidence for a 30 minute decision-to-delivery interval (DDI) standard, especially because randomized controlled trials are not possible on this subject. However, in addition to the limitations already outlined (confounding factors, Hawthorne effect, variable characterization of nonreassuring fetal heart rate [NRFHR], etc), the results of this study may not alter the current practice trend in the United States and the United Kingdom. This is because the prior belief about the validity and practicality of the arbitrary 30 minute standard has changed considerably, and a Bayesian approach in this respect is likely to be the norm.

In the United Kingdom, it took the anesthetists (who observed obstetricians’ distress) to test and propose a 4-category classification of timing of all cesareans, now accepted nationally. The emergency cesarean section for NRFHR would constitute the categories-1 and -2 cesareans (not to be confused with 3-tier fetal heart rate classification). Only those cases of NRFHR associated with a rapidly deteriorating pathological fetal heart rate pattern or an acute accident (abruption, cord prolapse, uterine rupture, etc) fall into the category 1 to which a 30 minute standard applies but with a further recommendation to deliver the baby even more expeditiously as possible. There is some confusion or lack of clarity about the DDI (30-90 minutes?) for category 2 cesareans for nondire NRFHR, and the author is currently conducting a study to test pertinent practical recommendations.

Unqualified adherence to the 30 minute standard increases the incidence of general anaesthesia, causes more distress to the patients/relatives, requires extra resources (already overstretched) around the clock, and has adverse medicolegal implications. Importantly, it also does not seem to have a scientific basis or a valid underlying hypothesis. Most NRFHRs in current practice indicate a potential for a serious fetal acidemia developing, if labor is allowed to continue. The vast majority of cases of NRFHR in the United States would be in the category 2 (of the 3-tier classification of fetal heart rate patterns) with some additional criteria. This pattern may need to be present for 30-60 minutes before the decision to intervene and could even be further observed if labor was progressing normally. Hence, there does not seem to be a valid hypothesis for an indiscriminate application of the 30 minute DDI. Rigid recommendations for DDI for NRFHR probably cannot be made, and some degree of individualization within the context of a 2-tier framework for emergency cesarean section for NRFHR seems desirable.