López-Zeno J A, Peaceman A M, Adashek J A, Socol M L
Department of Obstetrics and Gynecology, Northwestern University Medical School, Northwestern Memorial Hospital, Chicago, IL 60611.
N Engl J Med. 1992 Feb 13;326(7):450-4. doi: 10.1056/NEJM199202133260705.
Over the past two decades, the rate of cesarean section in the United States has risen from 5 percent to 25 percent of deliveries, primarily because of the increased frequency of dystocia (arrest of labor). One strategy that has been proposed for increasing the rate of vaginal delivery is a program of active management of labor that encourages early amniotomy, early diagnosis of slow progress in labor, and the use of higher than usual doses of oxytocin; the efficacy and safety of this approach are uncertain, however.
We conducted a randomized trial in which nulliparous women in spontaneous labor at term were randomly assigned to either active management of labor or traditional management. With active management, amniotomy was performed within one hour of the diagnosis of labor, and when the rate of cervical dilation was less than 1 cm per hour, oxytocin was infused at an initial rate of 6 mU per minute. The dose was increased by 6 mU per minute every 15 minutes (to a maximum of 36 mU per minute) until there were seven contractions every 15 minutes.
For the women assigned to active management (n = 351), the cesarean-section rate was 10.5 percent, as compared with 14.1 percent for those assigned to traditional management (n = 354, P = 0.18). The 26 percent reduction in the cesarean-section rate was due primarily to a decrease in dystocia. After we controlled for potential confounding variables, the reduction in the rate of delivery by cesarean section was statistically significant (odds ratio for women given active as compared with traditional management, 0.57; 95 percent confidence interval, 0.36 to 0.95). With active management, the average length of labor was shortened by 1.66 hours, principally because of earlier amniotomy and earlier use of oxytocin. There was no increase in maternal or neonatal morbidity, and there were significantly fewer infectious complications in the mothers.
The program we studied for the active management of labor reduces the incidence of dystocia and increases the rate of vaginal delivery without increasing maternal or neonatal morbidity.
在过去二十年中，美国剖宫产率已从分娩总数的5%上升至25%，主要原因是难产（产程停滞）发生率增加。为提高阴道分娩率而提出的一项策略是积极产程管理方案，该方案鼓励早期人工破膜、早期诊断产程进展缓慢以及使用高于常规剂量的缩宫素；然而，这种方法的有效性和安全性尚不确定。
我们进行了一项随机试验，将足月自然临产的初产妇随机分为积极产程管理组或传统管理组。在积极产程管理中，在诊断临产1小时内进行人工破膜，当宫颈扩张速度低于每小时1厘米时，以每分钟6毫单位的初始速度静脉滴注缩宫素。每15分钟将剂量增加6毫单位/分钟（最大至36毫单位/分钟），直至每15分钟有7次宫缩。
分配到积极产程管理组的妇女（n = 351）剖宫产率为10.5%，而分配到传统管理组的妇女（n = 354）剖宫产率为14.1%（P = 0.18）。剖宫产率降低26%主要是由于难产率下降。在我们控制了潜在的混杂变量后，剖宫产率的降低具有统计学意义（积极产程管理组与传统管理组相比，优势比为0.57；95%置信区间为0.36至0.95）。采用积极产程管理，平均产程缩短1.66小时，主要是因为更早进行人工破膜和更早使用缩宫素。孕产妇或新生儿发病率没有增加，母亲的感染并发症明显减少。
我们研究的积极产程管理方案可降低难产发生率，提高阴道分娩率，且不增加孕产妇或新生儿发病率。
