PLoS Biology (May 2020)

The haemodynamics of the human placenta in utero.

  • Neele S Dellschaft,
  • George Hutchinson,
  • Simon Shah,
  • Nia W Jones,
  • Chris Bradley,
  • Lopa Leach,
  • Craig Platt,
  • Richard Bowtell,
  • Penny A Gowland

DOI
https://doi.org/10.1371/journal.pbio.3000676
Journal volume & issue
Vol. 18, no. 5
p. e3000676

Abstract

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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.