Recent evidence that the placenta has its own community of microbes is now uncertain as it seems the experiments were corrupted by contamination
Source:
https://www.newscientist.com/article/2211529-the-human-placenta-may-not-have-a-microbiome-after-all/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home