The aim of the study is to analyse urethral mobility and excursion of the pubo-rectal angle, using perineal ultrasound, after normal vaginal delivery and water delivery. A total of 52 primiparous women were enrolled: 25 who had delivery in water (W Group), 27 who had delivery without using water (NW Group). Every woman underwent perineal ultrasound assessment at 6 months after having given birth. The following parameters were assessed: urethral mobility during Valsalva's manoeuvre, movement of the puborectal sling angle during contraction of the levator ani muscle. Data obtained show that the urethral mobility during Valsalva's manoeuvre is higher in the W Group (34.9 degrees) in comparison to the NW Group (29.5 degrees), without statistically significant differences. The excursion of the pubo-rectal sling angle resulted lower in the W Group (8.7 degrees) than in the NW Group (11.0 degrees), without statistically significant differences. The present study found no statistically differences in pelvic floor, using perineal ultrasound, between water and "non-water" delivery.