A digitized whole slide image of a placental membrane roll [low magnification; haemotoxylin and eosin (H&E) stain]. To illustrate relative scale, the blue square indicates a single blood vessel. B: Image patch showing an example of a healthy blood vessel (high magnification; H&E stain). C: Image patch showing a decidual arteriole affected by early-stage decidual vasculopathy, characterized by smooth hypertrophic muscle around the blood vessel lumen (high magnification; H&E stain). Scale bars: 125 um (B); 100 um (C). Original magnification, x20 (A).