We have used magnetic resonance imaging (MRI) to provide important new insights into the function of the human placenta in utero. We have measured slow net flow and high net oxygenation in the placenta in vivo, which are consistent with efficient delivery of oxygen from mother to fetus. Our experimental evidence substantiates previous hypotheses on the effects of spiral artery remodelling in utero and also indicates rapid venous drainage from the placenta, which is important because this outflow has been largely neglected in the past. Furthermore, beyond Braxton Hicks contractions, which involve the entire uterus, we have identified a new physiological phenomenon, the ‘utero-placental pump’, by which the placenta and underlying uterine wall contract independently of the rest of the uterus, expelling maternal blood from the intervillous space.

我们已经使用磁共振成像（MRI）为子宫内胎盘的功能提供重要的新见解。我们已经测量了体内胎盘的缓慢净流量和高净氧合，这与从母体到胎儿的有效氧输送是一致的。我们的实验证据证实了先前关于子宫内螺旋动脉重构影响的假说，并且还表明从胎盘快速排出静脉，这很重要，因为过去这种流出一直被忽略。此外，除了涉及整个子宫的布拉克斯顿·希克斯收缩之外，我们还发现了一种新的生理现象，即“子宫胎盘泵”，胎盘和基础子宫壁通过该现象独立于子宫的其余部分而收缩，从而排出了母体血液空隙空间。