Objective: Identify the prenatal determinants associated with cesarean delivery during labor of term breech presentation for which vaginal delivery is planned.
Study design: Prospective study of 174 French and Belgian maternity units. Relations between cesarean and prenatal determinants were estimated with a multilevel logistic model and expressed as adjusted ORs. A prediction score for cesarean section was proposed and diagnostic values were estimated for different cutoff values.
Results: Of 2,478 women meeting the inclusion criteria, 705 (28.5%) had cesarean deliveries. Nulliparity, complete breech, rupture of membranes before labor, fetal weight > or = 3800 g, biparietal diameter > 95 mm and university and public non-teaching hospital maternity units were significantly associated with cesarean delivery during labor. The rate of cesarean during labor was significantly higher in establishments where more than 80% of women had planned cesareans and in cases where mode of delivery had not been decided before labor. The prediction score values ranged from 9 to 21.4 (10th, 50th and 90th percentiles corresponded to 10.1, 12.2 and 14.7). The cesarean rate was 43% in women whose score was greater than the cutoff point of 12.9, and 15% for women whose score was below this value.
Conclusion: Our findings indicate that once vaginal delivery has been decided upon, the risk of cesarean delivery during labor for breech presentation at term depends not only on the progress of labor, but also on prenatal determinants both maternal and obstetrical. It also depends on some characteristics of the maternity units. Obstetricians should either plan cesarean delivery or define stringent rules for indications of cesarean during labor.