Warbler said:

I, for one, do not believe that the Levitical laws were inspired by God. They just don't make sense. Callings a woman's menstrual cycle, something they can't avoid doing, a sin??? An all knowing all powerful god would not be that stupid.

I wouldn't say that the text goes as far as saying it is a sin, but rather that it is uncleanliness. To keep the people of Israel in a state of Holiness, which is what the Levitical laws were for, the impurity of blood and menstruation must be dealt with.

Maybe you would call it semantics, but the difference seems clear to me.