Shearer E L
Soc Sci Med. 1993 Nov;37(10):1223-31. doi: 10.1016/0277-9536(93)90334-z.
Cesarean section rates have risen dramatically in the U.S. over the past 20 years. Although infant mortality has declined during the same period, there is little evidence that more frequent cesarean surgery is the cause. Cesareans save lives or benefit health in certain circumstances, but the incidence of those indications has not increased. Cesarean section also has risks, the most significant for the infant being iatrogenic prematurity or respiratory disease. Maternal mortality is 2-4 times higher and morbidity is 5-10 times higher after a cesarean compared to vaginal birth. The four indications responsible for most of the rise in cesarean rates--previous cesarean, dystocia, breech presentation, and fetal distress--are those conferring the least clear-cut benefit. Demographically, women who are most likely to experience pregnancy complications, low birth weight births, or infant mortality are least likely to have a cesarean. Social, economic, and other factors seem to have a greater influence on the decision to perform a cesarean than does expected medical benefit. The development of neonatal intensive care, expanded access to prenatal care, and greater availability of abortion and family planning have contributed more to falling infant mortality. It has been estimated that approximately half the cesareans currently performed in the U.S. are medically unnecessary, resulting in considerable avoidable maternal mortality and morbidity, and a cost of over $1 billion each year.
在过去20年里，美国的剖宫产率急剧上升。尽管同期婴儿死亡率有所下降，但几乎没有证据表明更频繁的剖宫产手术是其原因。剖宫产在某些情况下能挽救生命或有益于健康，但这些指征的发生率并未增加。剖宫产也有风险，对婴儿来说最显著的风险是医源性早产或呼吸系统疾病。与阴道分娩相比，剖宫产术后产妇死亡率高出2至4倍，发病率高出5至10倍。导致剖宫产率上升的主要四个指征——既往剖宫产史、难产、臀位和胎儿窘迫——是那些益处最不明确的指征。从人口统计学角度来看，最有可能经历妊娠并发症、低体重儿出生或婴儿死亡的女性进行剖宫产的可能性最小。社会、经济和其他因素似乎对剖宫产决策的影响比预期的医疗益处更大。新生儿重症监护的发展、扩大产前护理的可及性以及增加堕胎和计划生育服务，对降低婴儿死亡率的贡献更大。据估计，目前在美国进行的剖宫产手术中约有一半在医学上是不必要的，这导致了相当数量的可避免的产妇死亡率和发病率，每年的成本超过10亿美元。
