Birth trauma: incidence and predisposing factors.

The authors retrospectively studied 13,870 singleton full-term consecutive live births at a major teaching hospital and assessed the frequency of brachial plexus injury, clavicular fracture, and facial nerve injury in newborns delivered from January 1974 through December 1977 and from January 1979 through September 1981. Predisposing factors relating to mechanical birth trauma were defined, and a risk assessment profile was developed to identify the fetus at risk. Mechanical injuries were identified according to the International Classification of Diseases codes 761. The incidence of selected birth injuries in the study group were: brachial plexus injury, 2.6 per 1000 or 1 in 385 single full-term live births; fractured clavicle, 2.0 per 1000 or 1 in 495 single full-term live births; and facial nerve injury, 7.5 per 1000 or 1 in 133 single full-term live births. There were 162 full-term infants born with 168 injuries relevant to this study. Of the six infants who incurred more than one injury, three had a combined fractured clavicle-brachial plexus injury, and three had facial nerve-branchial plexus injuries. Logistic regression analysis of fetal, maternal, and intrapartum complications in labor and delivery revealed that midforceps , shoulder dystocia, low forceps, infants greater than 3500 g, and second stage labor exceeding 60 minutes were the predominant events associated with fetal injury. The authors then applied a risk assessment profile to successfully identify over 50% of the injured and 84% of the uninjured groups. From their results, the authors suggest that obstetricians should alert the pediatricians when these predisposing factors exist to aid in the recognition and early treatment of these birth injuries.