I am quite sure this is stress incontinence and is quite common in females no matter what you're age. Yes it does happen during pregnancy but there are other causes. If you participate in a lot of sports, are physically active or for some reason get hit in the bladder a lot you are more likely to get it. Yes there was something about the bladder getting moved and a pelvic floor muscle. And coughing, sneezing, laughing, running tends to make you release a little bit. I've heard that kegal exercises help and your doctor can help you out with this too. It's common so I'm sure they get this question all the time.

There are a ton of articles on the internet about stress incontinence. You may want to look at those.