Talk to your gyno about this. It's relatively normal, but if it's becoming burdensome, there are treatment options. I just use muscle training and awareness, but depending on how bad it is they may want to do surgery. I haven't heard good things about it though, so I'd never do that.
Try a poise pad if you think you need more protection. Regular maxis aren't made for holding urine, but if you don't need the full absorbancy of a pull-up, they are awfully hot in the summer.