In this study I have tried to establish the types of arterial division on the chorionic plate of human placenta, and the incidence rate of these types. The corrosion method was used to study 55 human placentas coming from normal full-term pregnancies. It was established that the dispersed or dichotomous type occurs, most frequently (38.2%) as a result of the division of arterial stem into two arteries, of about the similar diameters. The angles between the branches were measured. It was also established that branches of the umbilical arteries pass over the veins, parallelly to the fetal surface of the placenta, and these branches give arteries which supply placental cotyledons.

Keywords: human placenta, anatomic variations, Umbilical Arteries, chorionic plate