Tawaf al-Nisa'
Tawāf al-nisāʾ (طواف النساء) is a tawaf and a two rak'a prayer which is one of the obligatory rites of hajj al-tamattu' and al-'umra al-mufrada. It is only after tawaf al-nisa' that sexual pleasure from one's spouse becomes halal to him/her. Naming of this tawaf to nisa' (women) may suggest that it is only obligatory to men, however, this tawaf is obligatory to both men and women; just as after ihram sexual pleasure of one's spouse becomes forbidden to both genders.
It is not obligatory in 'umra al-tamattu'. However, on the basis of caution, it is better to perform tawaf al-nisa' followed by its prayer with the hope of reward before taqsir.
If one wore ihram with the intention of al-'umra al-mufrada, after the taqsir or halq they should perform tawaf al-nisa' and its prayer and only after that their spouse will be halal for them.
Ṭawāf al-nisāʾ and its prayer are obligatory but are not among the fundamental elements of hajj. Therefore, if a person neglects them deliberately, his hajj would not be void. However, his/her spouse will not be ḥalāl to him/her (he/she is not allowed to have any sexual pleasure from his/her spouse).
The manner and rulings of tawaf al-nisa' and its prayer are similar to those of tawaf and prayer of tawaf.