Objective: To describe a new system for classifying genital ambiguity and urogenital sinus abnormalities. Prader's classification (which attempts to describe the degree of masculinization) has been used for decades, while the urogenital sinus has generally been described as simply high or low; neither classification fits the spectrum of anomalies, nor do they allow for outcome data research.
Methods: An ideal description of genital ambiguity and urogenital sinus anomalies should include the degree of masculinization, phallic size, external genital appearance, and the true location of the vaginal confluence in relation to the bladder neck and the perineal meatus. We describe a new system to define these variables.
Results: In the PVE classification developed, P represents stretched phallic length and width, V the true vaginal location according to the distance from the bladder neck to the vagina and the distance from the vagina to the perineal meatus, and E the external genital appearance or Prader number.
Conclusions: The PVE classification system aids in surgical planning and will be helpful in the analysis of surgical outcomes of genital ambiguity and urogenital anomalies.