14 - Shoulder Dystocia

Abstract

Shoulder dystocia occurs when the fetal shoulder(s) does not deliver after initial attempts at extraction-oriented traction are unsuccessful or when ancillary obstetrical maneuvers are required to effect delivery. Many studies report a wide range of incidence of shoulder dystocia, but recent studies have demonstrated an incidence of about 1% of vaginal deliveries. While various risk factors or associations for shoulder dystocia have been identified, for the most part shoulder dystocia remains an unpredict­able and unpreventable event. For example, fetal macrosomia and maternal diabetes increase the risk for shoulder dystocia, but most cases occur in nondiabetic women with normal-sized infants. Women with prior shoulder dystocia are at particularly increased risk for recurrent shoulder dystocia. Shoulder dystocia is an obstetric emergency and may result in serious maternal and/or neonatal injury. Management requires prompt diagnosis along with implementation of appropriate maneuvers designed to alleviate the dystocia and minimize maternal/neonatal injury. Although no sequence or combination of maneuvers is superior, it is reasonable to begin with McRobert’s maneuver and suprapubic pressure, then move to direct fetal manipulation techniques based on the clinician’s training and experience. Since shoulder dystocia is relatively uncommon, simulations and team training facilitate exposure to the challenges and consequences of these high-risk events in a controlled teaching environment.