Research on the placenta as the interface between the mother and the fetus has been
undertaken for some 150 years, and in 2 subsequent reviews, we attempted to summarize
the situation. In the first part, we described the discovery of unique physiological
modifications of the uteroplacental spiral arteries, enabling them to cope with a major
increase in blood flow necessary to ensure proper growth of the fetus. These consist of an
invasion of the arterial walls by trophoblast and a progressive disappearance of its normal …