Kimberlin D F, Hauth J C, Owen J, Bottoms S F, Iams J D, Mercer B M, Thom E A, Moawad A H, VanDorsten J P, Thurnau G R
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Alabama at Birmingham, 35233-7333, USA.
Am J Obstet Gynecol. 1999 Mar;180(3 Pt 1):683-9. doi: 10.1016/s0002-9378(99)70273-5.
The aim of the study was to determine whether infants weighing </=1000 g after birth who are born to women who undergo indicated preterm delivery have different neonatal outcomes than do those born as a result of either spontaneous preterm labor or preterm premature rupture of membranes.
In a 1-year observational study (1992-1993) the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network collected outcome data for 799 infants whose birth weights were </=1000 g. Only singleton infants with gestational age >20 weeks who were not produced as the result of an induced abortion were included. Our analysis was further limited to infants without major congenital anomalies who survived >2 days, were deemed potentially viable by the obstetrician, and would have undergone a cesarean delivery for fetal indications (N = 411). The primary reason for delivery was categorized as indicated delivery, spontaneous preterm labor, or spontaneous preterm premature rupture of membranes. Selected neonatal outcomes were evaluated among infants born to women in each of these groups. Logistic regression analyses were used to control for the effects of other potentially confounding variables.
A total of 156 of the 411 infants were born to women who underwent an indicated preterm delivery, whereas 160 were born after spontaneous preterm labor and 95 were delivered after preterm premature rupture of membranes. Univariate analyses revealed significantly lower incidences of grade III or IV intraventricular hemorrhage, grade III or IV retinopathy of prematurity, and seizure activity among infants born in an indicated preterm delivery than among those born after spontaneous preterm labor or preterm premature rupture of membranes. However, infants of women who underwent indicated preterm delivery had a more advanced mean gestational age at birth than did those born after spontaneous preterm labor or preterm premature rupture of membranes (28 +/- 2 weeks, 26 +/- 2 weeks, and 26 +/- 1 weeks, respectively, P <.001). Multiple logistic regression analysis was therefore used to control for the disparity in gestational age. Multivariate analyses did not confirm the apparent improvement in neonatal outcome in the indicated delivery group.
In this population of infants weighing </=1000 g, selected neonatal outcomes did not differ according to birth by indicated preterm delivery, spontaneous preterm labor, or preterm premature rupture of membranes.
本研究旨在确定因医源性早产而出生的出生体重≤1000g的婴儿，其新生儿结局是否与因自然早产或胎膜早破而出生的婴儿不同。
在一项为期1年的观察性研究（1992 - 1993年）中，美国国立儿童健康与人类发展研究所母胎医学单位网络收集了799例出生体重≤1000g婴儿的结局数据。仅纳入孕龄>20周且非人工流产所致的单胎婴儿。我们的分析进一步局限于无严重先天性畸形、存活>2天、经产科医生判定有潜在存活能力且因胎儿指征本应行剖宫产的婴儿（N = 411）。分娩的主要原因分为医源性分娩、自然早产或自然胎膜早破。在这些组中出生的婴儿母亲所生的婴儿中评估选定的新生儿结局。采用逻辑回归分析来控制其他潜在混杂变量的影响。
411例婴儿中，共有156例出生于接受医源性早产的母亲，160例出生于自然早产之后，95例出生于胎膜早破之后。单因素分析显示，医源性早产出生的婴儿发生III级或IV级脑室内出血、III级或IV级早产儿视网膜病变以及惊厥活动的发生率显著低于自然早产或胎膜早破出生的婴儿。然而，接受医源性早产的母亲所生婴儿的出生平均孕龄比自然早产或胎膜早破出生的婴儿更接近足月（分别为28±2周、26±2周和26±1周，P<.001）。因此，采用多元逻辑回归分析来控制孕龄差异。多因素分析未证实医源性分娩组新生儿结局有明显改善。
在这群出生体重≤1000g的婴儿中，选定的新生儿结局在医源性早产、自然早产或胎膜早破出生的婴儿之间并无差异。
