Niddah in a Nutshell

The Basic Laws of Taharat Hamishpachah (Family Purity)

A woman enters the halachic status of niddah when she experiences uterine bleeding not due to abrasions, lacerations or other forms of trauma (makah). The most common cause of this status is menstruation. However, niddah and menstruation are not totally synonymous. Uterine bleeding from the withdrawal of hormones (such as occurs when using oral contraceptive pills), and as side effects of medication also causes the onset of this status. Stains (ketamim) found on the body, clothing or bedding that fit certain criteria and cannot be attributed to other sources also render a woman niddah. Certain gynecological procedures involving significant dilation of the cervix may render a woman niddah even in the absence of visible bleeding. Childbirth brings on a similar status known as yoledet.

While the wife is niddah, the couple is not permitted any physical contact. Further proscriptions on behavior (harchakot), apply as well. In order to prevent marital relations from inadvertantly taking place at the time that a woman begins her menses, the couple also observes times of separation (vestot or onot perishah) when marital relations are prohibited but the harchakot are not required.

A woman remains in the niddah status until she has passed the following stages:

1. At least five days (or four by some Sephardi customs), have passed since the onset of the niddah.
2. All bleeding has ceased. This is halachically confirmed by a self performed internal exam known as a hefsek taharah, and further confirmed by the insertion of a cloth from sunset until dark (moch dachuk). As mentioned, the hefsek taharah may be performed as early as the fifth day from the onset of the niddah status.
3. She counts seven clean days (shivah neki'im), beginning the day after the hefsek taharah. During these days, the woman wears white underwear and performs internal exams (bedikot) (generally two per day) to halachically assure that bleeding has not restarted.
4. On the completion of the seven days, she prepares for immersion, ensuring that she has removed all barriers (chatzitzot) which could intervene between her body and the water. She then immerses in a kosher mikveh and exits the niddah status. She is now tehorah and may resume relations with her husband.