Table 1 A 3 × 3 grid system used for charting in the Pelvic Organ Prolapse Quantification (POP-Q) system regarding where six points are located with reference to the plane of the hymen in: two on the anterior vaginal wall (points Aa and Ba), two at the apical vagina (points C and D), and two on the posterior vaginal wall (points Ap and Bp). The genital hiatus (Gh), perineal body (Pb), and total vaginal length (TVL) are also measured. All POP-Q points, except TVL, are measured during patient's Valsalva maneuver and reflect maximum protrusion [11]

From: Management of preexisting pelvic organ prolapse in pregnancy complicated with preterm premature rupture of membrane: a case report