Neilson James P
Cochrane Pregnancy & Child Birth Group, Liverpool Women's Hospital, Liverpool, UK.
Obstet Gynecol. 2008 Jul;112(1):177-8. doi: 10.1097/AOG.0b013e31817f2169.
Policies for timing of cord clamping vary, with early cord clamping generally carried out in the first 60 seconds after birth, whereas later cord clamping usually involves clamping the umbilical cord greater than one minute after the birth or when cord pulsation has ceased.
To determine the effects of different policies of timing of cord clamping at delivery of the placenta on maternal and neonatal outcomes.
We searched the Cochrane Pregnancy and Child Birth Group's Trials Register (December 2007).
Randomized controlled trials comparing early and late cord clamping.
Two review authors independently assessed trial eligibility and quality and extracted data.
We included 11 trials of 2,989 mothers and their babies. No significant differences between early and late cord clamping were seen for postpartum hemorrhage or severe postpartum hemorrhage in any of the five trials (2236 women) which measured this outcome (relative risk (RR) for postpartum hemorrhage 500 mls or more 1.22, 95% (CI) 0.96 to 1.55). For neonatal outcomes, our review showed both benefits and harms for late cord clamping. Following birth, there was a significant increase in infants needing phototherapy for jaundice (RR 0.59, 95% CI 0.38 to 0.92; five trials of 1,762 infants) in the late compared with early clamping group. This was accompanied by significant increases in newborn hemoglobin levels in the late cord clamping group compared with early cord clamping (weighted mean difference 2.17 g/dL; 95% CI 0.28 to 4.06; three trials of 671 infants), although this effect did not persist past six months. Infant ferritin levels remained higher in the late clamping group than the early clamping group at six months.
AUTHORS' CONCLUSION: One definition of active management includes directions to administer an uterotonic with birth of the anterior shoulder of the baby and to clamp the umbilical cord within 30-60 seconds of birth of the baby (which is not always feasible in practice). In this review delaying clamping of the cord for at least two to three minutes seems not to increase the risk of postpartum hemorrhage. In addition, late cord clamping can be advantageous for the infant by improving iron status which may be of clinical value particularly in infants where access to good nutrition is poor, although delaying clamping increases the risk of jaundice requiring phototherapy.
脐带结扎时机的政策各不相同,早期脐带结扎通常在出生后的头60秒内进行,而延迟脐带结扎通常是在出生后一分钟以上或脐带搏动停止时结扎脐带。
确定胎盘娩出时不同脐带结扎时机政策对母婴结局的影响。
我们检索了Cochrane妊娠与分娩组试验注册库(2007年12月)。
比较早期和延迟脐带结扎的随机对照试验。
两位综述作者独立评估试验的合格性和质量并提取数据。
我们纳入了11项涉及2989名母亲及其婴儿的试验。在测量该结局的五项试验(2236名女性)中的任何一项中,早期和延迟脐带结扎在产后出血或严重产后出血方面均未观察到显著差异(产后出血500毫升及以上的相对风险(RR)为1.22,95%置信区间(CI)为0.96至1.55)。对于新生儿结局,我们的综述显示延迟脐带结扎既有益处也有危害。出生后,与早期结扎组相比,延迟结扎组中因黄疸需要光疗的婴儿显著增加(RR 0.59,95%CI 0.38至0.92;五项试验,共1762名婴儿)。与早期脐带结扎相比,延迟脐带结扎组新生儿血红蛋白水平也显著升高(加权平均差2.17 g/dL;95%CI 0.28至4.06;三项试验,共671名婴儿),尽管这种影响在六个月后并未持续。六个月时,延迟结扎组婴儿的铁蛋白水平仍高于早期结扎组。
积极管理的一个定义包括在婴儿前肩娩出时给予宫缩剂并在婴儿出生后30 - 60秒内结扎脐带的指导(在实际操作中这并不总是可行的)。在本综述中,延迟脐带结扎至少两到三分钟似乎不会增加产后出血的风险。此外,延迟脐带结扎对婴儿可能有利,因为它可以改善铁状态,这可能具有临床价值,特别是在营养状况不佳的婴儿中,尽管延迟结扎会增加需要光疗的黄疸风险。