I don't know what is considered 'frequent' for medical/etc. purposes - but I go every hour or two all night (about every three hours during the day). I would consider that frequent, since it interrupts my schedule. My baby is real low now though, and I started out going pretty often anyway - even when not pregnant I'd get up at least once every night to go to the bathroom - it seems to be a family thing, my teenaged sister gets up at least once a night too (I know 'cause she lived with us this past summer).