Candidate predictors of cesarean delivery
Univariable analyses revealed the following variables were significantly associated with the probability of caesarean delivery: maternal height, BMI before labor, induction of labor, bilateral femoral head distance, interspinous diameter, obstetric conjugate, subpubic angle, fetal biparietal diameter, fetal head circumference and fetal abdominal circumference (Table 2). Subsequent backward stepwise multivariable logistics analysis identified maternal BMI before labor (OR, 1.307; 95% CI, 1.109-1.541; P = 0.001), induction (OR, 2.777; 95% CI, 1.190-6.478; P = 0.018), bilateral femoral head distance (OR, 0.898; 95% CI, 0.838-0.963; P = 0.003), obstetric conjugate (OR, 0.951; 95% CI, 0.907-0.997; P = 0.038), fetal head circumference (OR, 1.786; 95% CI, 1.152-2.770; P = 0.01) and fetal abdominal circumference (OR, 1.685; 95% CI, 1.221-2.325; P = 0.001) as independent predictors for the risk of cesarean delivery (Table 3).