Erb/Duchenneʼs Palsy: A Consequence of Fetal Macrosomia and Method of Delivery

Methods of delivery, maternal and neonatal characteristics were examined to determine their role in the occurrence of Erb/Duchenneʼs palsy. Data from 210,947 Washington state birth certificates from 1980 through 1982 were examined. The incidence was 50.2 cases of Erbʼs palsy per 100,000 live births. A case control study design was used to analyze 106 cases and 386 controls by both univariable and multivariable analysis. Birth weight was shown to be a significant risk factor regardless of which method of delivery was used. A high birth weight infant (4001–4500 g) had 2.5 times the risk of incurring an upper brachial plexus injury compared with normal size infants (2501–4000 g). The risk for infants greater than 4500 g increased another tenfold (OR = 21.0). When birth weight was controlled for in the analysis, midforceps (OR = 18.3), vacuum extraction (OR = 17.2), and low forceps (OR = 3.7) remained significantly associated with the Erbʼs palsy. Delivery by cesarean section was associated with a significant protective effect (OR = 0.5) compared with instrumental vaginal delivery. These data demonstrate a high risk for serious birth injury associated with instrumental midpelvic delivery.