Does the 'iddah period differ in the case of khulʿ from that of divorce, and is the 'iddah obligatory if the woman is certain of the emptiness of her womb, given that the 'iddah was legislated for the purpose of ensuring the emptiness of the womb?

The majority of jurists hold that the waiting period (iddah) for a woman who has sought divorce (khulʿ) is the same as that for a divorced woman. However, some scholars are of the opinion that the waiting period for a woman who has sought divorce is one menstrual cycle. The waiting period is obligatory for a woman when its cause exists, whether she knows her womb is clear or not, and it has many rulings.