Zavah

Torah sources for the zavah are sourced in the book of Leviticus (Leviticus 15:1-15, Leviticus 15:25-33).

According to textual scholars, the regulations concerning childbirth,(Leviticus 12) which have a similar seven-day waiting period before washing, and the sin and whole offerings, were originally suffixed to those concerning menstruation, but were later moved.[1] Although the zavah regulations clearly have a sanitary benefit in the light of modern medical knowledge, Biblical scholars see these regulations as having originally derived from taboos against contact with blood and semen, because they were considered to house life and were consequently considered sacred;[2] the seven-day period is thought to exist to ensure that the abnormality has genuinely ceased, the sin offering is considered to have originally been made as an apology for violating the taboo.[3]

According to the Jerusalem Talmud, the eleven-day period between each [monthly] menstrual cycle is Halakha LeMoshe MiSinai.[4] This has been explained by Maimonides[5] to mean that seven days are given to all women during their regular monthly menstrual cycle, known as the days of the menstruate (Hebrew: niddah), even if her actual period lasted only 3 to 5 days. From the eighth day after the beginning of her period (the terminus post quem, or the earliest date in which they begin to reckon the case of a zavah), when she should have normally concluded her period, these are days that are known in Hebrew as the days of a running issue (Hebrew: zivah), and which simply defines a time (from the 8th to the 18th day, for a total of eleven days) that, if the woman had an irregular flow of blood for three consecutive days during this time, she becomes a zavah and is capable of defiling whatever she touches, and especially whatever object she happens to be standing upon, lying upon or sitting upon.

Zavah gedolah

In the zavah gedolah (major zavah) scenario, the woman, within an eleven-day window of the completion of her base seven-day niddah period (and immersion in the mikveh) notices an abnormal blood discharge.[6] If the next day another discharge is noticed, followed by yet another discharge on the third consecutive day, she is deemed a zavah gedolah. She is then required to count seven clean days, immerse in a mikveh on the seventh day and bring a korban on the eighth.

Due to the destruction of the Temple in Jerusalem, Judaism regards the sacrificial regulations as being in abeyance; rabbinical tradition subsequently differentiated less between the regulations of zavah and those for niddah.

In Orthodox Judaism nowadays, zavah (an abnormal discharge) and niddah (healthy menstruation) are no longer distinguished. A menstruating woman (niddah) is required to wait the seven additional clean days that she would if she were a zavah.

Conversely, Reform Judaism regards such regulations as anachronistic; adherents of Conservative Judaism take a view somewhere between these views, with opinions in favor of returning to the Biblical distinction between niddah (ending seven days from the beginning of a normal menstrual period) and zavah (ending seven days after the end of an abnormal discharge).

• Zav