Background: The aim of this longitudinal study was to determine the short-term and long-term effects of spontaneous and forceps delivery on bladder neck (BN) support. Methods: One hundred twenty-seven primiparae women underwent repeated clinical and perineosonography examinations during pregnancy and at 10 weeks and 10 months after delivery. Eighty-two had a spontaneous delivery, 25 a forceps delivery, and 20 cesarean section. The parameters measured by perineosonography were BN position measured in a two-axis system in the supine and standing positions, BN mobility, and BN elevation during pelvic floor squeezing. Results: At 10 weeks and 10 months after delivery, a significant posterior, but not inferior, displacement of the BN at rest in the supine and standing positions was observed only after spontaneous delivery. In spontaneous and forceps-delivered women, but not in cesarean-delivered women, BN mobility stayed significantly increased and the ability to elevate the BN during voluntary pelvic floor contraction significantly decreased 10 weeks and 10 months after delivery. Women with cystocoeles grade 1 and 2 had significant higher bladder neck mobility compared with women without cystocoele. Conclusions: Vaginal delivery is responsible for a significant and persistent impairment of BN support. Forceps delivery does not seem to have a more deleterious effect than spontaneous delivery.