Perimetrium

The perimetrium (or serous coat of uterus) is the outer serosa layer of the uterus, equivalent to peritoneum. It is embrionically derived from visceral peritoneum. Perimetrium consists of superficial mesothelium, and a thin layer of loose connective tissue beneath it. Posterior surface of the uterus is completely covered by the perimetrium, but anterior surface only partially.