中文摘要：

目的分析总结临床资料，探讨引起晚期早产儿发生的母亲孕期风险因素，以期为降低晚期早产儿发生率提供临床指导依据。方法选择2010年10月1日～2011年9月30日人住北京军区总医院附属八一儿童医院的晚期早产儿为研究对象，对母亲孕期状况进行调查问卷，加以总结分析，经多因素相关分析，得出相关因素。结果晚期早产儿以胎龄35周为多，与胎龄34周和36周两组比较，差异有高度统计学意义（P〈0．01）。与晚期早产儿发生密切相关的母亲孕期状况有12种，不同胎龄发生的风险因素不完全相同。胎龄34周者，主要与孕期无明显异常、胎膜早破、妊娠高血压、胎盘早剥密切相关（P〈0．05）。胎龄35周者，主要与孕期无明显异常、胎膜早破、妊娠高血压、官内窘迫、胎盘早剥和羊水异常密切相关（P〈0．05）。胎龄36周者，除了以上6种外，还与感染性疾病、妊娠糖尿病、双胎及多胎妊娠和前置胎盘相关（P〈0．05）。结论影响晚期早产儿发生的母亲孕期状况主要有：孕期无明显异常、胎膜早破、妊娠高血压、胎盘早剥、宫内窘迫、羊水异常、双胎或多胎妊娠、感染性疾病、妊娠糖尿病、前置胎盘、瘢痕子宫和先兆流产史。不同胎龄的母亲孕期相关因素不完全相同，3个胎龄中都包括孕期无明显异常、胎膜早破、妊娠高血压、胎盘早剥因素，相关性最强的前3位是孕期无明显异常、胎膜早破、妊娠高血压。

英文摘要：

Objective To analyze and summarize clinical data, investigate the risk factors of mothers during pregnancy result to late-preterm infants be born, in order to provide clinical evidence for decreasing incidence rate of late-preterm infant. Methods Late-preterm infants born in preterm NICU of Bayi Children＇s Hospital, Military General Hospital of Beijing People＇s Liberation Army from 1 October 2010 to 30 September 2011 were chosen. The mothers of late- preterm infants in the hospital NICU were investigated. The risk factors were analyzed by Logistic analysis. Results The incidence rate of gestational age 35 weeks was most, compared to gestational age 34 weeks and 36 weeks, the difference was statistically significant （P 〈 0.01）. 12 kinds of risk factors of mothers during pregnancy involved in resulting to late-preterm infants be born, the risk factors were different among different gestational ages. The risk factors that non apparent abnormality, premature rupture of mem- branes, gestational hypertension and placental abruption were closer correlation to gestational age 34 weeks infants （P 〈 0.05）. The risk factors that non apparent abnormality, premature rupture of membranes, gestational hypertension, intrauterine embar rassment, placental abruption and amniotic fluid abnormality were closer correlation to gestational age 35 weeks infants （P 〈 0.05）. There were anther 4 kinds of risk factors, including twins or multiple pregnancy, infectious diseases, gestational diabetes mel litus and placenta praevia, besides above 6 risk factors were closer correlation to gestational age 36 weeks infants （P 〈 0.05）. Conclusion Risk factors of mothers during pregnancy closer correlation to late-preterm infants be born include non apparent abnormality, premature rupture of membranes, gestational hypertension, placental abruption, intrauterine embarrassment, am- niotic fluid abnormality, twins or multiple pregnancy, infectious diseases, gestational diabetes mellitus, placenta praevia, scar uterus and th