Shoulder dystocia: an update.

Shoulder dystocia has no consensus definition or management algorithm. Its incidence ranges from 0.2% to 3% and its occurrence is unpredictable. Risk factors for shoulder dystocia may include macrosomia, maternal diabetes, operative vaginal delivery, history of macrosomic infant or shoulder dystocia, labor abnormalities, post-term pregnancy, maternal obesity, advanced maternal age, fetal anthropometric variations, and male fetal gender. Once identified, multiple maneuvers can be applied in a stepwise fashion in an attempt to alleviate the dystocia. While training clinicians to manage shoulder dystocia is difficult because of its rare occurrence and lack of standardized management, all clinicians must be able to manage shoulder dystocia at any time.