Norwegian Institute of Public Health, Oslo, Norway;
Norwegian Institute of Public Health, Oslo, Norway.
Pediatrics. 2019 Feb;143(2). doi: 10.1542/peds.2018-0933.
Survival of infants born at the limit of viability varies between high-income countries.
To summarize the prognosis of survival and risk of impairment for infants born at 22 + 0/7 weeks' to 27 + 6/7 weeks' gestational age (GA) in high-income countries.
We searched 9 databases for cohort studies published between 2000 and 2017 in which researchers reported on survival or neurodevelopmental outcomes.
GA was based on ultrasound results, the last menstrual period, or a combination of both, and neurodevelopmental outcomes were measured by using the Bayley Scales of Infant Development II or III at 18 to 36 months of age.
Two reviewers independently extracted data and assessed the risk of bias and quality of evidence.
Sixty-five studies were included. Mean survival rates increased from near 0% of all births, 7.3% of live births, and 24.1% of infants admitted to intensive care at 22 weeks' GA to 82.1%, 90.1%, and 90.2% at 27 weeks' GA, respectively. For the survivors, the rates of severe impairment decreased from 36.3% to 19.1% for 22 to 24 weeks' GA and from 14.0% to 4.2% for 25 to 27 weeks' GA. The mean chance of survival without impairment for infants born alive increased from 1.2% to 9.3% for 22 to 24 weeks' GA and from 40.6% to 64.2% for 25 to 27 weeks' GA.
The confidence in these estimates ranged from high to very low.
Survival without impairment was substantially lower for children born at <25 weeks' GA than for those born later.
在高收入国家，极早产儿的存活率存在差异。
总结高收入国家胎龄 22+0/7 周至 27+6/7 周的极早产儿的存活率和生存后受损风险的预后。
我们检索了 9 个数据库，纳入了 2000 年至 2017 年发表的队列研究，这些研究报告了生存或神经发育结局。
胎龄基于超声结果、末次月经或两者的组合，神经发育结局采用贝利婴幼儿发育量表第二版或第三版在 18 至 36 个月时进行测量。
两位审查员独立提取数据，并评估了偏倚风险和证据质量。
共纳入 65 项研究。平均存活率从所有分娩的近 0%、活产的 7.3%和重症监护入院的 24.1%，分别增加到 27 周时的 82.1%、90.1%和 90.2%。对于幸存者，22 至 24 周胎龄的严重受损率从 36.3%下降到 19.1%，25 至 27 周胎龄的严重受损率从 14.0%下降到 4.2%。出生时存活且无损伤的婴儿的平均机会从 22 至 24 周的 1.2%增加到 9.3%，从 25 至 27 周的 40.6%增加到 64.2%。
这些估计的置信度从高到极低不等。
与晚期出生的婴儿相比，胎龄<25 周的婴儿无损伤存活的可能性明显较低。
