Shoulder dystocia: fifteen years' experience in a community hospital.

The profile of the patient most likely to present with shoulder dystocia was determined to be a patient over 41 weeks' gestation with a prolonged decelerative phase of labor (8 to 10 cm) who was receiving epidural anesthesia before adequate descent of the vertex, resulting ina midforceps delivery. The patho-anatomic mechanism involves displacement of the anterior shoulder from a larger, i.e., oblique diameter, to a small (anteroposterior) diameter of the pelvis. The restitution of the shoulders to the oblique diameter is the hallmark of management. Proposed is an algorithm involving abdominal pressure to widening the episiotomy (bilateral if necessary) to displace the shoulders to the oblique diameter by corkscrewing or, if possible, careful delivery of the posterior shoulder. Cleidotomy is downplayed. The constant awareness of the possibility of the rapid development of shoulder dystocia, with its potentially lethal and always dangerous consequences, is espoused.