1995至2002年美国产妇试产及与试产相关的新生儿患病率和病死率趋势

目的:目前剖宫产后未经试产的重复剖宫产率不断上升。本研究拟探讨美国产妇试产率的下降与新生儿出生结局之间的关系。方法:采用1995至2002年间美国出生登记资料进行分析。选取既往剖宫产术分娩过一次单胎的产妇作为研究对象。通过多元logistic回归估算试产率高和低的两个时段中, 新生儿不良出生结局与试产之间的调整OR值。结果:本研究共选取了1833407名研究对象。美国既往剖宫产产妇再次分娩时的试产率从1995年的38.5%降低至2002年的15.0%。在此期间产妇的基线资料没有发生具有统计学意义的改变。既往剖宫产产妇再次分娩时未经试产会增加新生儿发生窒息死亡和患病的风险。通过分析试产率最低的2002年的数据, 发现该风险在低危产妇中仍然存在。结论:美国产妇剖宫产后再次分娩时试产率下降导致了新生儿不良结局的发生率上升。

Secular trends in trial of labor and associated neonatal mortality and morbidity in the United States, 1995 to 2002

Objective: A proportion of elective repeated cesarean sections where a trial of labor in a uterus with a previous scar was not attempted is on the increase. This study aimed to assess how reduced the use of trial of labor has impacted on neonatal outcomes in the United States.
Methods: Pregnant women with one previous cesarean delivery and a singleton live birth of the index pregnancy were abstracted from the 1995 to 2002 birth registration data of the United States. Adjusted odds ratios for adverse neonatal outcomes of trial of labor were estimated by multiple logistic regression models, in overall study subjects and in the two periods with high and low rates of trial of labor.
Results: A total of 1833407 eligible subjects were included in the analysis. Rate of trial of labor after one previous cesarean section dropped from 38.5% in 1995 to 15.0% in 2002. No significant change was observed in the patient population profile. Successful vaginal birth after cesarean delivery (VBAC) also declined from 76.6% in 1995 to 66.0% in 2002. A trial of labor after one previous cesarean section was correlated with increased risks of asphyxia-related neonatal death and neonatal morbidity. This risk was even more pronounced in low risk women and in the last study years with the lowest rate of trial of labor.
Conclusion: The reduced use of trial of labor after one cesarean delivery in recent years in the United States has actually resulted in increased risk of adverse neonatal outcomes associated with a trial of labor.