Garite Thomas J, Kurtzman James, Maurel Kimberly, Clark Reese
Pediatrix Medical Group, Sunrise, FL; Department of Obstetrics and Gynecology, University of California, Irvine, College of Medicine, Irvine, CA, USA.
Am J Obstet Gynecol. 2009 Mar;200(3):248.e1-9. doi: 10.1016/j.ajog.2009.01.021.
Previous studies using repetitive courses of antenatal corticosteroids (ACS) have demonstrated marginal or no benefit and concern over potential risk. No prior prospective or randomized studies have evaluated the option of a single rescue course of ACS on neonatal outcome.
A multicenter randomized double-blind placebo-controlled trial was performed from May 2003 through February 2008 in 18 private (15) and university (3) medical centers. Patients with singletons or twins < 33 weeks who had completed a single course of ACS before 30 weeks and at least 14 days before inclusion, and were judged to have a recurring threat of preterm delivery in the coming week, were included. Patients were randomized to receive a single rescue course of betamethasone, 2 12-mg doses 24 hours apart, or placebo. Exclusion criteria included: premature rupture of membranes, advanced dilation (> 5 cm), chorioamnionitis, and other steroid use.
In all, 437 patients were randomized (223 rescue steroid group and 214 placebo group). A total of 55% of patients in each group delivered at < 34 weeks. There was a significant reduction in the primary outcome of composite neonatal morbidity < 34 weeks in the rescue steroid group vs placebo (43.9% vs 63.6%; odds ratio, 0.45; 95% confidence interval, 0.27-0.75; P = .002) and significantly decreased respiratory distress syndrome, ventilator support, and surfactant use. Perinatal mortality and other morbidities were similar in each group. Including all neonates in the analysis (regardless of gestational age at delivery) still demonstrated a significant reduction in composite morbidity in the rescue course group (32.1% vs 42.6%, odds ratio, 0.65; 95% confidence interval, 0.44-0.97; P = .0034) and improvement in respiratory morbidities.
Administration of a single rescue course of ACS before 33 weeks improves neonatal outcome without apparent increased short-term risk.
既往使用重复疗程产前糖皮质激素（ACS）的研究显示获益甚微或无获益，且存在对潜在风险的担忧。此前尚无前瞻性或随机研究评估单次挽救性疗程ACS对新生儿结局的影响。
2003年5月至2008年2月在18家私立（15家）和大学（3家）医疗中心进行了一项多中心随机双盲安慰剂对照试验。纳入单胎或双胎妊娠且孕周<33周、在30周前且纳入前至少14天已完成单次ACS疗程、且被判定在未来一周有再次早产风险的患者。患者被随机分为接受单次挽救性疗程倍他米松（2剂12 mg，间隔24小时）或安慰剂。排除标准包括：胎膜早破、宫口开大>5 cm、绒毛膜羊膜炎及其他类固醇使用情况。
共437例患者被随机分组（223例挽救性类固醇组和214例安慰剂组）。每组中共有55%的患者在<34周时分娩。挽救性类固醇组与安慰剂组相比，<34周时复合新生儿发病率这一主要结局显著降低（43.9%对63.6%；比值比，0.45；95%置信区间，0.27 - 0.75；P = 0.002），且呼吸窘迫综合征、呼吸机支持及表面活性剂使用显著减少。每组围产期死亡率及其他发病率相似。将所有新生儿纳入分析（无论分娩时孕周）仍显示挽救性疗程组复合发病率显著降低（32.1%对42.6%，比值比，0.65；95%置信区间, 0.44 - 0.97；P = 0.0034），且呼吸疾病有所改善。
在33周前给予单次挽救性疗程ACS可改善新生儿结局，且无明显短期风险增加。
