The term Niddah means separation. During her menstrual flow and for several days thereafter, a Jewish woman is considered Niddah -- separate from her husband and unable to practice the sacred rituals of Judaism. Purification in a miqveh (a ritual bath) following her period restores full status as a wife and member of the Jewish community. In the contemporary world, debates about Niddah focus less on the literal exclusion of menstruating women from the synagogue, instead emphasizing relations between husband and wife and the general role of Jewish women in Judaism.

Although this has been...