Anatomy of the Placenta Umbilcal arteries Orch tlood (Oppor bioo Smooth chorion Amrochorone remhrnne At birth 500 g Choronic plate 15-25 cm Diameter 3 cm thick Anchoringⅷli Decidual septa 15-20 Cotyledons Myometrium Endometr EndometrialAnatomy of the Placenta ▪ At birth 500 g ▪ 15-25 cm Diameter ▪ 3 cm thick ▪ Anchoring villi ▪ Decidual septa → 15-20 Cotyledons