How is the waiting period for Ila' calculated if the husband is prevented from intercourse?

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If a husband vows Ila' (abstinence) and an impediment prevents him from intercourse, such as his illness, imprisonment, state of Ihram, or fasting, the waiting period is calculated from the moment of his vow. This is because the impediment originates from him, and the wife fulfilled her duty of making herself available. Consequently, if she made herself available and he abstained due to an impediment, her maintenance (Nafaqah) remains obligatory. If such impediments arise after the vow or if the husband becomes insane, the waiting period does not stop, due to the reason previously stated.