Changes in vesical neck mobility following vaginal delivery

To assess changes in urethral movement during the Valsalva maneuver and pelvic floor muscle contraction following vaginal delivery.

In a prospective repeated-measures study, 25 primigravidas, 20 multiparas, and ten women who were to have elective cesarean delivery were examined sonographically at 36-42 weeks of pregnancy and 6-10 weeks after delivery. Vesical neck position at rest and excursion during Valsalva maneuver and maximum pelvic muscle contraction were measured with perineal ultrasound. Data about resting bladder neck position and bladder neck elevation at contraction were compared with findings in age-matched nulligravid volunteers.

The bladder neck was significantly lower at rest in women after vaginal delivery than in those who had an elective cesarean delivery and in nulligravid controls. Bladder neck mobility had increased during the Valsalva maneuver in 16 of 25 primigravidas and 15 of 20 multiparas 6-10 weeks after vaginal delivery. The ability to elevate the vesical neck during pelvic muscle contraction was decreased in six of 25 primigravidas and in two of 20 multiparas 6-10 weeks after birth. Two women, one primigravid and one para 2 (with a previous elective cesarean delivery), both of whom had forceps delivery, completely lost the ability to contract voluntarily the pelvic floor muscles.

Vaginal delivery alters vesical neck descent during the Valsalva maneuver, and the ability of the pelvic muscles to elevate the urethra in some women.