Oneliner_1570

OneLiner

During sexual differentiation in the embryo (week six), there are two pairs of genital ducts: Mullerian (paramesonephric) and Wolffian (mesonephric). In normal female development, the ovary secretes estrogen which leads to Wolffian duct regression and preservation of the Mullerian duct. The Mullerian duct is responsible for the development of the upper vagina, uterus, and fallopian tubes. In Mayer–Rokitansky–Küster–Hauser syndrome (MRKH), there is spontaneous degeneration of the paramesonephric (Mullerian) duct and therefore agenesis of the upper vagina, which presents as a blind vaginal pouch on physical exam. Notably, patients still have normal ovaries and can produce estrogen, which leads to normal secondary sexual characteristics (breast and pubic hair development).