The permanent organs of the adult are preceded by a set of structures that are purely embryonic and that, with the exception of the ducts, disappear almost entirely before the end of fetal life.These embryonic structures are on either side: the pronephros, the mesonephros and the metanephros of the kidney, and the Wolffian and Müllerian ducts of the sex organ.[4] The female urethra is located between the bladder neck to the external urethral orifice and is behind the symphysis pubis.Causes for these disorders include congenital anomalies, infectious diseases, trauma, or conditions that secondarily involve the urinary structure.To gain access to the body, pathogens can penetrate mucous membranes lining the genitourinary tract.