The incidence of cardiac arrest during pregnancy is estimated to be about 1 in 30,000 pregnancies.4 According to a review of reported perimortem cesarean deliveries from 1985 to 2004, the most frequent causes are trauma, cardiogenic, emboli (e.g., amniotic fluid and air), magnesium overdose, sepsis, anesthesia, eclampsia, spontaneous uterine rupture, and intracranial hemorrhage.2