Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, Austria.
J Reprod Immunol. 2023 Aug;158:103985. doi: 10.1016/j.jri.2023.103985. Epub 2023 Jun 28.
For obvious reasons, in vivo measurements of placental oxygenation are extremely rare and hence, scientists need to focus on the few studies that revealed at least some data on the topic. The scarcity of real in vivo data resulted in the development of hypotheses on placental oxygenation that blocked an objective view on the topic for decades. Only now, new hypotheses are emerging adding new views and ideas on the topic. Especially in the field of preeclampsia, hypotheses on placental oxygenation have mislead a whole generation of scientists. This review article displays the available in vivo placental oxygen data from 8 to 40 weeks of gestation. It also compares these physiological oxygen concentrations, called physioxia, with the situation in pre-placental hypoxia, i.e. pregnancies at high altitude. Finally, it summarizes what we know today about oxygen measurements in cases with preeclampsia. In early-onset preeclampsia cases, all in vivo data available today point to increased oxygen values in the intervillous space of the placenta. This is due to a reduced oxygen transfer of the placental barrier from maternal to fetal blood, resulting in hypoxia of fetal blood and the fetus.
由于显而易见的原因，对胎盘氧合的体内测量极为罕见，因此，科学家们需要专注于那些至少揭示了一些相关主题数据的少数研究。由于缺乏真实的体内数据，导致了对胎盘氧合的假说的发展，这些假说在几十年里阻碍了对这一主题的客观看法。直到现在，新的假说正在出现，为这一主题增加了新的观点和想法。特别是在子痫前期领域，对胎盘氧合的假说误导了整整一代科学家。本文展示了 8 至 40 孕周的胎盘氧合的可用体内数据。它还将这些生理氧浓度（称为低氧血症）与前置胎盘缺氧的情况（即高海拔妊娠）进行了比较。最后，它总结了我们今天在子痫前期病例中对氧测量的了解。在早发型子痫前期病例中，目前所有可用的体内数据都表明胎盘绒毛间隙中的氧值增加。这是由于胎盘屏障的氧气从母体向胎儿血液的转移减少，导致胎儿血液和胎儿缺氧。
