Management of Suspected Cephalopelvic Disproportion

Initial Assessment and Diagnosis

The American College of Obstetricians and Gynecologists recommends proceeding directly to cesarean delivery when cephalopelvic disproportion (CPD) is confirmed or cannot be ruled out, as the risks of maternal and fetal damage are too great to attempt vaginal delivery 1, 2
Serial suprapubic palpation of the base of the fetal skull is essential to differentiate true descent from molding alone, and is the most critical examination technique in diagnosing CPD 1, 2
CPD occurs in 40-50% of all active phase arrest cases and 25-30% of cases with active phase disorders, making it a primary consideration in labor abnormalities 1, 2

Maternal factors associated with CPD include maternal diabetes and maternal obesity 1, 2
Fetal factors associated with CPD include macrosomia, malposition, malpresentation, marked asynclitism, and excessive molding without descent 1, 2

When CPD is confirmed or cannot be ruled out, proceed directly to cesarean delivery, as recommended by the American College of Obstetricians and Gynecologists 1, 2
Oxytocin augmentation is absolutely contraindicated in the presence of CPD, as it risks uterine hyperstimulation, uterine rupture, severe maternal lacerations, excessive fetal molding, and potential asphyxia without achieving vaginal delivery 1, 2
Operative vaginal delivery should not be attempted when CPD is confirmed, as it represents a clear contraindication 1

For women with skeletal dysplasia, cesarean delivery is recommended as the standard approach, as pelvic anatomy precludes vaginal delivery 3, 4, 1

Fetal head circumference ≥34.8 cm has 88% sensitivity and 74% specificity for predicting CPD requiring cesarean section 1

Advanced 3D/4D sonography and other imaging techniques to assess spatial relationships between fetal skull and maternal pelvis are still under investigation, as current diagnostic methods for CPD remain imperfect, according to the American College of Obstetricians and Gynecologists 5, 6