From an analysis of 11 abdominal pregnancy-related deaths and an estimated 5221 abdominal pregnancies in the United States, we estimated that there were 10.9 abdominal pregnancies per 100,000 live births and 9.2 per 1000 ectopic pregnancies; the mortality rate was 5.1 per 1000 cases. Although the risk of having an ectopic pregnancy is rising, the risk of abdominal pregnancy, which is probably always a sequel of a missed ruptured ectopic pregnancy, is apparently declining; this may be due to improved prenatal care. However, only one of nine women who reached the hospital alive had an accurate preoperative diagnosis of abdominal pregnancy, which suggests that preventing abdominal pregnancy-related death may depend, at least in part, upon increasing physicians' awareness of its clinical features.