Abstract
A brief description is given of the significance of gross and histological abnormalities of the placenta. The question of placental ageing is discussed and the possible ill-effects of inflammation and immune-mediated damage to the placenta considered. Finally, the pathology of the utero-placental vasculature is outlined, and the view is expressed that most cases of apparent ‘placental insufficiency’ are, in reality, due to maternal vascular insufficiency.