- Subject's leading edge of POP is at or beyond the hymen. At or beyond the hymen is defined as POP-Q scores of Ba ≥ 0 or Bp ≥ 0 or C ≥ 0 (for prolapse of the apical compartment alone) or C ≥ -½ total vaginal length (for a multi-compartment prolapse that includes the apical compartment).