Bird Stephen D
Department of Obstetrics and Gynaecology, The University of Melbourne, Australia.
Eur J Obstet Gynecol Reprod Biol. 2017 Jan;208:61-70. doi: 10.1016/j.ejogrb.2016.11.005. Epub 2016 Nov 11.
The artificial placenta (AP) has for many decades captured the imagination of scientists and authors with popular fiction including The Matrix and Aldous Huxley's "Brave New World", depicting a human surviving ex-utero in an artificial uterine environment (AUE). For scientists this has fascinated as a way forward for extremely preterm infants (EPIs) born less than 28 weeks of gestation. Early successes with mechanical ventilation (MV) for infants born above 28 weeks of gestation meant that AP research lost momentum. More recently, the gestational age limit for survival now borders on 23 weeks and corresponds to the biological milestone of lung development marked by the early canalicular stage of lung morphogenesis. The so called greyzone of 23-25 weeks represents a steep increase in mortality with decreasing gestational age and current options in neonatal care are on the fringes of efficacy for this population. A shift in thinking recognizes the vitality of EPIs as a fetus rather than a 37-40 week neonate and this has reinvigorated the concept of the AP. This review will discuss the scale of extreme preterm birth with special reference to previable infants born in the greyzone. Recent AP studies using sheep models are compared, technical obstacles discussed and future research themes identified.
几十年来，人工胎盘一直吸引着科学家们的想象力，也出现在包括《黑客帝国》和奥尔德斯·赫胥黎的《美丽新世界》等通俗小说中，描绘了人类在人工子宫环境（AUE）中在子宫外存活的情景。对科学家来说，这是为妊娠不足28周的极早产儿（EPI）开辟的一条前进道路，令人着迷。对于妊娠28周以上出生的婴儿，机械通气（MV）早期取得的成功意味着人工胎盘研究失去了动力。最近，存活的孕周下限已接近23周，这与肺发育的生物学里程碑相对应，即肺形态发生的早期小管期。23至25周的所谓灰色地带代表着随着孕周的减少死亡率急剧上升，而目前新生儿护理的选择对这一人群的疗效甚微。思维的转变认识到极早产儿作为胎儿而非37至40周新生儿的生命力，这重新激发了人工胎盘的概念。本综述将讨论极早产的规模，特别提及灰色地带出生的未成熟婴儿。比较了最近使用绵羊模型的人工胎盘研究，讨论了技术障碍并确定了未来的研究主题。
