Objective: Cesarean section (CS) rates continue to rise throughout the developed world. The aim of this study was to highlight variations in obstetric populations and practices and to identify variations in CS rates in different institutions.
Study design: Data from 9 institutional cohorts (total, 47,402; range, 1962-7985) from 9 different countries were examined using a 10-group classification system based on 4 characteristics of every pregnancy, namely single/multiple, nulliparity/multiparity, multiparity with CS scar, spontaneous/induced labor onset and term (>or=37 weeks) gestation.
Results: Overall CS rates correlated with CS rates in singleton cephalic nullipara (r = 0.992; P < .001). Whereas CS rates in induced labor were similar, greatest institutional variation were seen in spontaneously laboring multiparas (6.7-fold difference) and nulliparas (3.7-fold difference).
Conclusion: Ten-group analysis of international obstetric cesarean practice identifies wide variations in women in spontaneous cephalic term labor, a low-risk cohort amenable to effective intrapartum corrective intervention.