The Laws of Niddah: Taharat Hamishpaha
The Bible prohibits sex between a man and a menstruating woman.
Reprinted with permission from Every Person's Guide to Jewish Sexuality, published by Jason Aronson Publishers.
Jewish law forbids a husband to be intimate with his wife during the time of her menstrual cycle (generally from five to seven days), and extends the prohibition beyond this time for another seven days (known as the "seven clean days"). The laws concerning sexual separation are known as the laws of family purity (taharat hamishpaha in Hebrew). These laws of separation are based upon the biblical laws in the Torah (Leviticus 18:19 and 20:18) that prohibit sexual relations between husband and wife during the woman's menstrual period.
The Bible teaches: "Do not come near a woman when she is tamay from a menstrual period as seven days" (Leviticus 15:19). A woman in this state is called a niddah (menstruous woman). Birth also renders a woman a niddah. There is an entire tractate of the Talmud called Niddah, which deals with the laws relating to the ritual uncleanliness of a woman caused by menstruation.
Subsequent Jewish laws also forbid any bodily contact that might stimulate sexual excitement and lead to lovemaking. Thus, for example, it is not unusual for an Orthodox married couple to sleep in separate beds during this forbidden period.
When the state of niddah ends, the woman is required to immerse herself in a mikveh (ritual bath). This customarily takes place on the night after the completion of the so‑called "seven clean days." The water of the mikveh has to come from [water that has not been drawn with a vessel, for example,] a natural spring or river. Most mikvehs today are located in buildings, although a lake, river, or ocean can serve as a valid mikveh.
Before the immersion, the woman must cleanse herself thoroughly so that no foreign body clings to her and prevents the water from coming into direct contact with her body. The woman then immerses herself in the mikveh while totally unclothed and recites a blessing to God "who has sanctified us with His commandments and commanded us concerning immersion."
According to Jewish law, the only unmarried woman who is expected to go to the mikveh is a bride just before her wedding. It is a custom in some Jewish traditions that the groom, too, also be immersed in the mikveh. (Some traditional Jewish men also periodically immerse themselves in the mikveh, especially before the onset of the Sabbath or before other Jewish holidays.)
Rabbinic commentators and modern day psychologists have often posited that the observance of the laws of niddah makes for a happier marriage. It requires that the husband be considerate of his wife during the periods when her bodily chemistry undergoes a change. At the same time, it teaches the wife to regard her intimate relations with her husband not as a way of gratifying her physical desires but rather as a fulfillment of God's plan.