Measurements made in the midsagittal plane during magnetic resonance imaging (MRI). A, lowest point of the anterior vaginal wall; C, lowest point of the uterine cervix or vaginal stump, P, lowest point of the posterior vaginal wall, PB, front edge of the perineal body, SCIPP line, sacrococcygeal inferior pubic point line; PICS line, pelvic inclination correction line; LH, levator hiatus; UGH, urogenital hiatus