That's a really good question! I have no idea how you would know. My SIL was telling me last week that when she went in for her 2nd or 3rd baby, they were going to break her water only to find out it was already done! She didn't even know it! And she definitely wasn't swimming. Hopefully some other mamas will have good advice for you.
Speaking of swimming...
I was just going to start a thread about this! I hope it's not hijacking...but I have a question. I try to walk a few times a week, but gravity is starting to take it's toll on me. I'd like to start swimming regularly (weightless!), but I have no idea where to start. I know it's easy to get tired and not realize it. What's a good goal, minute-wise or otherwise? Should I just do laps? I'm not a great swimmer, but I can move in the water, and that's all I really need, right? TIA, and sorry for hijacking!