ACOG’s own consensus statement identifies the most common reasons a first C-section is performed, in order of frequency: labor dystocia (labor stalling out), abnormal or indeterminate fetal heart rate readings, fetal malpresentation, multiple gestation, and suspected large fetal size. The first two of those — labor dystocia and abnormal fetal heart rate tracing — together account for more than half of all primary cesarean deliveries. Both are judgment calls, not objective thresholds. Whether a labor has genuinely “stalled” or a fetal heart rate pattern is concerning enough to act on depends on how an individual clinician reads an ambiguous situation — which is exactly the kind of decision that varies by training, institutional culture, and individual risk tolerance.

Staffing model appears to matter too. Hospitals using a “laborist” model — where a hospital-employed obstetrician manages labor and delivery for whoever is in the unit, rather than each patient’s own private-practice physician juggling office hours and deliveries — have shown lower cesarean delivery rates in several studies compared to the traditional private-practice model, though the effect isn’t uniform everywhere it’s been tried.

Here’s the honest correction worth making to the most common assumption: it’s tempting to think financial incentive explains all of this — C-sections cost roughly 50% more than vaginal births, so surely higher rates mean more revenue. ACOG’s own current guidance says the evidence doesn’t actually support that as a primary driver, and specifically cites a Canadian study that switched obstetricians from fee-for-service to salary-based pay and found no resulting drop in C-section rates. The popular “it’s about the money” explanation is less supported by real evidence than culture, judgment, and staffing model.