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. The period, three months after a divorce and four months and ten days after the death of a spouse, is calculated on the number of menses that a woman has. Iddah was intended to ensure that the male parent of any offspring produced after the cessation of a nikah would be known.

Qur'an prohibits widows to engage themselves for four lunar months and ten days after the death of their husbands. Islamic scholars consider this directive to be a balance between mourning of husband's death and protecting the widow from criticism that she might be subjected to from re-marrying too quickly after her husband’s death. This is also to ascertain whether a woman is pregnant or not, since four and a half months is half the length of a normal pregnancy.

Husbands should make a will in favor of their wives for the provision of one year’s residence and maintenance, unless the wives themselves leave the house or take any other similar step.