Amrah, daughter of Abdur-Rahman ibn Saad ibn Zurarah, reported on the authority of Habibah, daughter of Sahl al-Ansariyyah: She (Habibah) was the wife of Thabit ibn Qays ibn Shimmas. The Messenger of Allah ﷺ came out one morning and found Habibah by his door. The Messenger of Allah ﷺ said: Who is this? She replied: I am Habibah, daughter of Sahl. He asked: What is your case? She replied: I and Thabit ibn Qays, referring to her husband, cannot live together. When Thabit ibn Qays came, the Messenger of Allah ﷺ said to him: This is Habibah, daughter of Sahl, and she has mentioned (about you) what Allah wished to mention. Habibah said: Messenger of Allah, all that he gave me is with me. The Messenger of Allah ﷺ said to Thabit ibn Qays: Take it from her. So he took it from her, and she lived among her people (relatives).
Hadith Referenceسنن ابي داود / كتاب تفريع أبواب الطلاق / 2227
1؎: This was the first khul‘ (dissolution of marriage at the wife’s request) in Islam. Through khul‘, the marriage is annulled. The waiting period (‘iddah) for khul‘ is one menstrual cycle (hayd). According to some scholars, one divorce (talaq) takes effect through khul‘; therefore, in their view, its waiting period is like that of divorce, i.e., three menstrual cycles. The first opinion is the preferred one.
´It was narrated from Yahya bin Sa'eed, from 'Amrah bint 'Abdur-Rahman, that she told him about Habibah bint Sahl:` "She was married to Thabit bin Qais bin Shammas. The Messenger of Allah went out to pray As-Subh and he found Habibah bint Sahl at his door at the end of the night. The Messenger of Allah said: 'Who is this?' She said: 'I am Habibah bint Sahl, O Messenger of Allah.' He said: 'What is the matter?' She said: 'I cannot live with Thabit bin Qais' -her husband. When Thabit bin Qais came, the Messenger of Allah said to him: 'Here is Habibah bint Sahl and she has said what Allah willed she should say.' Habibah said: 'O Messenger of Allah, everything that he gave me is with me.' The Messenger of Allah said: 'Take it from her.' So he took it from her and she stayed with her family."
Hafiz Muhammad Ameen
(1) A woman’s seeking divorce from her husband is called khul‘. In such a case, if the husband wishes, he may demand the return of the dower (mahr) or other gifts he had given to his wife; however, he cannot take anything more than this from the woman’s personal property. After reconciliation, the husband will pronounce divorce, after which reconciliation (ruju‘) will not be possible; however, if both wish, they may remarry after the waiting period (‘iddah).
(2) Although the outward form of khul‘ resembles divorce (talaq) in that the husband pronounces divorce at the wife’s request, in reality, khul‘ is an annulment (fasakh) of the marriage. Therefore, its waiting period (‘iddah) is not three menstrual cycles, but one menstrual cycle. The purpose of this is istibra’ al-rahim, i.e., to ascertain whether the woman is pregnant or not. If menstruation occurs, it means she is not pregnant, and thus she may remarry. If menstruation does not occur, it means she is pregnant. In this case, she cannot remarry until the child is born. See: (Hadith: 3527, 3528). According to the Hanafis, khul‘ is considered a divorce (talaq), so its waiting period is three menstrual cycles, but this position is not correct.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 3492