Difficult delivery of the impacted fetal head during cesarean section: intraoperative disengagement dystocia

Cesarean section is commonly perceived as a simple and safe alternative to difficult vaginal birth. However, several trends in obstetrical practice may act in concert to cause impaction of the fetal head during the second stage of labor or, more commonly, following failed instrumental delivery. Subsequently, difficult and potentially traumatic disengagement of the deeply wedged head during cesarean section occurs. The maneuvers to disengage the wedged head include pushing (bimanual or by an assistant) the head through the vagina or, alternatively, pulling the infant's feet through the uterine incision. Although both methods may cause serious maternal and neonatal complications, available data seem to favor the pulling method and better outcome seems to depend on adequate uterine relaxation, the patient's position during operation, and special attention to the uterine incision. More data are needed to establish the frequency and extent of intraoperative disengagement dystocia and to determine the management protocol that carries the lowest risk in such circumstances.