The placenta as the tree of lifeBMJ 2016; 354 doi: https://doi.org/10.1136/bmj.i3805 (Published 16 August 2016) Cite this as: BMJ 2016;354:i3805
- Silvia Chiarelli, professor of pathology,
- Ludovica Sandei, medical doctor
- Department of Medicine (DIMED), University of Padova, Italy
The helical course of the umbilical vessels was recorded by Jacobus Berengarius in 1521, and in 1600 Hieronymus Fabricius ab Acquapendente provided the first illustrations in his book De formatu foetu.
Both left and right helices may occur in the umbilical cord; the left:right ratio is 7:1, while absent coiling …