Alternative method of sampling placentas for the assessment of uteroplacental vasculature.

A new method for the taking and embedding of placental blocks to obtain maximum information regarding the uteroplacental vasculature was developed. This method involves taking en face blocks of the basal plate of the placenta. Results show that normal and abnormal maternal vessels are clearly delineated. In addition to conventional full thickness blocks, which provide information about the chorionic plate such as inflammation and meconium pigment uptake, and about the parenchyma in the other zones remote from the basal plate of the placenta, it is recommended that en face blocks be taken for histological assessment of the placenta.