Guasch X Demestre, Torrent F Raspall, Martínez-Nadal S, Cerén C Vila, Saco M J Elizari, Castellví P Sala
SCIAS-Hospital de Barcelona, España.
An Pediatr (Barc). 2009 Oct;71(4):291-8. doi: 10.1016/j.anpedi.2009.06.011. Epub 2009 Jul 31.
There has been a gradual rise in prematurity rates recent years, almost exclusively at the expense of the late preterm (34 to 36 weeks). This population, although with less risk than smaller preterm gestational age, has a morbidity rate significantly higher than term infants. However, there is some underestimation regarding developments in the short and long term. The aim of this study was to look at the incidence of prematurity in our institution and to analyze morbidity and mortality in late preterm compared with term infants
We performed a retrospective review of newborns in our Hospital from January 1992 until December 31, 2008. Late preterm group was defined as between 34(0/7) and 36(6/7) weeks gestation (N=2003) and term infants from 37 to 42 weeks gestation (N=32015). We formed 2 subgroups according two time periods (1992-1998 and 2000-2008). The morbidity and mortality for each of the groups and subgroups, and the morbidity from week 34 to 42, were analysed and compared.
During the period studied, the prematurity rate increased from 3.9% to 9.8%, exclusively at the expense of the late preterm (79%). The rate of mortality in late preterm was 5 per thousand compared to 1.1 per thousand in the term (P <0.0001, OR 4.71, 95% CI 2.3-9.5). The incidence of admission to the Neonatal Unit, Cesarean rate, twin, respiratory disorders, need for respiratory support in the form of nasal CPAP or mechanical ventilation, incidence of apnea, jaundice requiring phototherapy, hypoglycaemia and need for parenteral nutrition were significantly higher (P<0.0001) in the late preterm group compared with term infants. The morbidity rate decreased significantly as gestational age increased, with the lowest value from 39 weeks.
Morbidity and mortality in late preterm infants is significantly higher than in term infants. The guidelines for these near term premature babies need to be reviewed, looking for possible causes of prematurity, and trying to reduce their impact, as well as developing a protocol for their care and close monitoring to minimize the associated morbidity. There should be long-term monitoring to find out the consequences on their psychomotor development. The obstetrics group should be made aware of the true risks of births in the near-term gestational ages.
近年来早产率呈逐渐上升趋势，几乎完全以晚期早产（34至36周）率上升为代价。这一群体虽然比孕周更小的早产儿风险低，但发病率显著高于足月儿。然而，在短期和长期发育方面存在一些低估情况。本研究的目的是观察我院的早产发生率，并分析晚期早产儿与足月儿相比的发病率和死亡率。
我们对我院1992年1月至2008年12月31日期间的新生儿进行了回顾性研究。晚期早产组定义为孕周在34（0/7）至36（6/7）周之间（N = 2003），足月儿为孕周37至42周（N = 32015）。我们根据两个时间段（1992 - 1998年和2000 - 2008年）分成了2个亚组。分析并比较了每个组和亚组的发病率和死亡率，以及从第34周到42周的发病率。
在研究期间，早产率从3.9%上升至9.8%，完全以晚期早产率上升（79%）为代价。晚期早产儿的死亡率为千分之五，而足月儿为千分之一（P < 0.0001，比值比4.71，95%可信区间2.3 - 9.5）。与足月儿相比，晚期早产组新生儿入住新生儿重症监护病房的发生率、剖宫产率、双胎率、呼吸系统疾病、需要经鼻持续气道正压通气或机械通气形式的呼吸支持、呼吸暂停发生率、需要光疗的黄疸、低血糖以及需要肠外营养的发生率均显著更高（P < 0.0001）。发病率随着孕周增加而显著降低，在39周时最低。
晚期早产儿的发病率和死亡率显著高于足月儿。需要重新审视这些近足月早产儿的诊疗指南，寻找早产的可能原因，并努力降低其影响，同时制定他们的护理和密切监测方案，以尽量减少相关发病率。应进行长期监测，以了解对其心理运动发育的影响。应让产科团队了解近足月妊娠分娩的真实风险。
