Anderson G M, Lomas J
N Engl J Med. 1984 Oct 4;311(14):887-92. doi: 10.1056/NEJM198410043111405.
We analyzed the records of 454,668 births in Ontario in the years 1979 to 1982 and found that the cesarean birth rate increased from 16.5 per hundred deliveries in 1979 to 18.7 in 1982. Cesarean births were classified according to four indications: previous cesarean birth, breech presentation, dystocia, and fetal distress. The increase in the cesarean rate for each indication from 1979 to 1982 was calculated and expressed as a percentage of the total rate increase. Previous cesarean births accounted for 68 per cent of the increase, breech presentation for 14 per cent, dystocia for 4 per cent, and fetal distress for 14 per cent. The impact of previous cesarean births was indicated by an increase in the number of women presenting with this indication--from 5.8 to 7.8 per cent of all deliveries. Although the incidence of breech presentation remained stable, the cesarean birth rate increased from 54.8 to 65 per cent for this indication. There were no marked changes in either the incidence of or cesarean rates for dystocia. The incidence of fetal distress doubled (2.4 to 4.7 per cent of deliveries), but the rate of cesarean births in these cases fell from 50.5 to 32.7 per cent. These findings suggest that physicians may have begun to respond to rising professional and public concern over the increasing cesarean birth rate, but major advances in controlling this rate can be achieved only by addressing the question of vaginal deliveries for some patients who have previously had cesarean section.
我们分析了1979年至1982年安大略省454,668例出生记录，发现剖宫产率从1979年每100例分娩中的16.5例上升至1982年的18.7例。剖宫产根据四个指征分类：既往剖宫产史、臀位、难产和胎儿窘迫。计算了1979年至1982年每个指征的剖宫产率增幅，并表示为总增幅的百分比。既往剖宫产史占增幅的68%，臀位占14%，难产占4%，胎儿窘迫占14%。既往剖宫产史的影响表现为出现该指征的女性数量增加——从所有分娩的5.8%增至7.8%。尽管臀位发生率保持稳定，但该指征的剖宫产率从54.8%升至65%。难产的发生率和剖宫产率均无明显变化。胎儿窘迫的发生率翻倍（从分娩的2.4%增至4.7%），但这些病例的剖宫产率从50.5%降至32.7%。这些发现表明，医生可能已开始回应专业人士和公众对不断上升的剖宫产率的日益关注，但只有解决一些既往有剖宫产史患者的阴道分娩问题，才能在控制这一比率方面取得重大进展。
