The same happens to me, involuntary leaking. My bladder gets to a certain level then just empties with no warning. I also have urgency. I had my sling done 2 years ago and i'm now looking for a surgeon to remove my sling. I am doing pelvic floor exercises 3 times a day, a little better but hasn't helped the involuntary leaks. I hate this and i'm depressed as it has taken over my life. I am in talks with two uro's and neither are keen to remove the sling. I want it out, continue with pelvic floor and possibly have bulking agents put in. All talks at the mo, but i wished i had never had the sling done.