Iddah

In Islam, iddah or iddat (Arabic: العدة‎; period of waiting) is the period a woman must observe after the death of her spouse or after a divorce, during which she may not marry another man. Its purpose is to ensure that the male parent of any offspring produced after the cessation of a nikah (marriage) would be known. The length of iddah varies according to a number of circumstances.

The iddah of a woman divorced by her husband is three monthly periods, unless she is pregnant in which case the ‘iddah lasts until she gives birth, or unless the marriage was not consummated in which case there is no `iddah, or unless she does not menstruate, in which case "the scholars say that she should observe an ‘iddah of a full year, nine months for pregnancy and three months for ‘iddah."

For a woman whose husband has died, the `iddah is four lunar months and ten days after the death of their husbands, whether or not the marriage was consummated. The period, four months and ten days after the death of a spouse, is calculated on the number of menses that a woman has.