average perineum

How Long Is The Average Female Perineum? The average perineal body length was 3.90 cm (+/-0.70). Patients with a perineal body of < or = 2.5 cm had a significantly higher chance of sustaining a third- or fourth-degree laceration (40% vs. 5.6%, P=. 004). What is considered a short perineum? According to the perineal length,