How to express Catamenia in the daily usage?

Cleveland   Thu Aug 09, 2007 8:19 pm GMT
it's quite hard to get to know how to express this kind of things in the daily usage if you are not a female, so how to say Catamenia and related things? are there some oral words for them?

and PS: is "it's quite hard to get to know...." a correct expression? it sounds odd when I read it again.
Divvy   Thu Aug 09, 2007 9:14 pm GMT
Menstruation. The/a period. Time of the month.