My ex used to stop me saying she feels like peeing during penetrative sex

This was ex from a couple of years ago. Almost every time we had penetrative sex, she used to stop me after 10 minutes saying she feels like peeing. I have had sex with a few other girls who have told me the same too. So, to all the girls out there who feel this same the same way during sex what do I make of this ? Is it that you guys are reaching orgasm and feel an urge to pee, or is it squirting ? Please explain