[Osteogenic metaplasia or residual embryonic endometrial ossification?]

There are only about 90 cases described in the literature of the presence of an intra-uterine osseous structure--so the condition is not a common one. Often the aetiology is unknown. The purpose of this work is to describe the clinical picture and the anatomo-pathological characteristics on one form which leaves practically no doubt as to how the presence of bony structures in the uterus arise. We call this residual endometrial-ossification (O.R.E.) and note osteogenic or osseous metaplasia. We define O.R.E. as the presence of an osseous structure inside the uterus which does not arise from metaplasia of the cells of the endometrium.