Judism

When we were studing Judism there were some pretty strange things that I learned.  One was, I found that the Jewish have a fear of menstrual blood, they feel they will be contaminated by it.  Anyone who touches a women who is on her period will be considered unclean until night time, and they must wash themselves and wash their clothing.  I failed to find out why women are unclean longer if they have a girl rather than a boy, but I found this website which explains a lot more about everything.  http://www.womenpriests.org/traditio/unclean.asp