Abstract
This study was done to test the hypothesis that simulated vaginal birth by vaginal distension (VD) causes more severe urinary incontinence and slower recovery in diabetic rats. After measuring baseline leak point pressure (LPP) in 16 diabetes mellitus (DM) and 16 age- and weight-matched control (Ct) female Sprague-Dawley rats, these animals underwent either VD or sham VD (sham). Four and ten days after the procedures, LPP and conscious cystometry were assessed. Tissues were then harvested and examined by light microscopy. LPP at baseline was equal among all four groups. Four days after VD, LPP in both VD groups dropped to significantly lower levels than in sham rats (P < 0.001). Moreover, LPP in the DM+VD group was significantly lower than in the Ct+VD group. At 10 days, LPP in the Ct+VD group had recovered to its baseline value, whereas the LPP in the DM+VD group remained significantly reduced. DM rats had larger bladder capacity and longer voiding intervals than Ct rats. Histological findings included more severe damage to the external sphincter striated musculature of the urethra in DM+VD group compared with Ct+VD. In conclusion, these findings suggest that DM causes increased severity and delayed functional recovery from the effects of simulated childbirth.