If they experience the menstruation flow how then could one notice if you are fertile or not
you can see a fertility specialist. a fertility doctor can do tests to see if you should have any problems concieving.
an infertile woman will still experiance periods.... theres no way to know for sure if one was infertile unless they underwent specific testing... Dont ever listen to someone who says "We dont have to use protection because im not fertile" Its very rare for someone to actually know this- many people have thought they were infertile and have ended up pregnant