Now in our 13th year of bringing you beautiful imagery from biomedical science every day

Search the archive of over 4000 images

Passing Through
08 February 2017

Passing Through

The placenta is a vital connection that provides a foetus with nutrients from its mother’s blood. However, if the placenta forms incorrectly it can endanger the lives of both mother and foetus. Syncytial knots are pieces of shed tissue from the developing placenta – one is shown here (bright circle) in the lining of the uterus. If these reach the mother’s bloodstream they can cause sudden death. Nonetheless, the placenta doesn’t block all cells from the foetus from passing through to the mother. Foetal cells known as extravillous trophoblasts (EVTs) do cross over, and scientists have recently found that they enter the mother’s bloodstream earlier than previously thought. This crossing helps shape the border between the mother’s bloodstream and the placenta. The EVTs could also be helping the mother’s immune system get accustomed to the foetus’s cells, and prevent it attacking them.

Written by Esther Redhouse White

Search The Archive

Submit An Image

Follow on Tumblr

Follow on Instagram

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.