Badawi N, Kurinczuk J J, Keogh J M, Alessandri L M, O'Sullivan F, Burton P R, Pemberton P J, Stanley F J
TVW Telethon Institute for Child Health Research, PO Box 855, West Perth, Western Australia 6872, Australia. nadiaBnch.edu.au
BMJ. 1998 Dec 5;317(7172):1554-8. doi: 10.1136/bmj.317.7172.1554.
To identify intrapartum predictors of newborn encephalopathy in term infants.
Population based, unmatched case-control study.
Metropolitan area of Western Australia, June 1993 to September 1995.
All 164 term infants with moderate or severe newborn encephalopathy; 400 randomly selected controls.
Adjusted odds ratio estimates.
The birth prevalence of moderate or severe newborn encephalopathy was 3.8/1000 term live births. The neonatal fatality was 9.1%. Maternal pyrexia (odds ratio 3.82), a persistent occipitoposterior position (4.29), and an acute intrapartum event (4.44) were all risk factors for newborn encephalopathy. More case infants than control infants were induced (41.5% and 30.5%, respectively) and fewer case infants were delivered by caesarean section without labour (3.7% and 14.5%, respectively). Operative vaginal delivery (2.34) and emergency caesarean section (2.17) were both associated with an increased risk. There was an inverse relation between elective caesarean section (0.17) and newborn encephalopathy. After application of a set of consensus criteria for elective caesarean section only three (7%) eligible case mothers compared with 33 (65%) eligible control mothers were sectioned electively. Of all the case infants, 113 (69%) had only antepartum risk factors for newborn encephalopathy identified; 39 (24%) had antepartum and intrapartum factors; eight (5%) had only intrapartum factors; and four (2%) had no recognised antepartum or intrapartum factors.
The causes of newborn encephalopathy are heterogeneous and many relate to the antepartum period. Elective caesarean section has an inverse association with newborn encephalopathy. Intrapartum hypoxia alone accounts for only a small proportion of newborn encephalopathy. These results question the view that most risk factors for newborn encephalopathy lie in the intrapartum period.
确定足月儿产时新生儿脑病的预测因素。
基于人群的非匹配病例对照研究。
西澳大利亚州大都市地区，1993年6月至1995年9月。
164例患有中度或重度新生儿脑病的足月儿；400例随机选取的对照。
调整后的比值比估计值。
中度或重度新生儿脑病的出生患病率为3.8/1000例足月儿活产。新生儿病死率为9.1%。产妇发热（比值比3.82）、持续性枕后位（4.29）和急性产时事件（4.44）均为新生儿脑病的危险因素。与对照婴儿相比，更多的病例婴儿接受了引产（分别为41.5%和30.5%），而未经历分娩而行剖宫产的病例婴儿较少（分别为3.7%和14.5%）。产钳助产（2.34）和急诊剖宫产（2.17）均与风险增加相关。择期剖宫产（0.17）与新生儿脑病呈负相关。应用一组择期剖宫产的共识标准后，只有3例（7%）符合条件的病例母亲接受了择期剖宫产，而符合条件的对照母亲中有33例（65%）接受了择期剖宫产。在所有病例婴儿中，113例（69%）仅发现有新生儿脑病的产前危险因素；39例（24%）有产前和产时因素；8例（5%）只有产时因素；4例（2%）没有公认的产前或产时因素。
新生儿脑病的病因是多方面的，许多与产前时期有关。择期剖宫产与新生儿脑病呈负相关。单纯产时缺氧仅占新生儿脑病的一小部分。这些结果对新生儿脑病的大多数危险因素存在于产时这一观点提出了质疑。
