Supernumerary ovary: embryology.

This paper documents the fourteenth-ever recorded case of supernumerary ovary, and the second-largest reported thus far, a spherical 6 x 5 x 4 cm convoluted mass. Histologic examination revealed a hemorrhagic corpus luteum cyst within normal limits. Proposed mechanisms of formation are discussed, but definitive evidence of origin remains elusive. Although the presence of a supernumerary ovary may be clinically significant, many are overlooked, emphasising the importance of vigilance at laparotomy.