The Messenger of Allah ﷺ said, "Women are not required to shave their heads. Women are only required to trim their hair."
قال رسول الله ﷺ: ليس على النساء حلق، إنما على النساء التقصير.
Abu Dawud narrated it through two routes. The first (1985) is from Abu Yaqub Baghdadi, trustworthy, who said, Hisham bin Yusuf told us, from Ibn Jurayj, from Abdul-Hameed bin Jubayr bin Shayba, from Safiya bint Shayba, who said, Umm Uthman bint Abu Sufyan told me that Ibn Abbas said (then he mentioned it).Daraqutni (2666) and Bayhaqi (5/104) both narrated it through two routes, from Hisham bin Yusuf, from Ibn Jurayj, who said, Abdul-Hameed bin Jubayr told me, with his chain, similarly. Its isnad is sahih, and its narrators are trustworthy. Hisham bin Yusuf is Sanani, Abu Abdul-Rahman the judge, trustworthy, one of the narrators found in the Sahih.Umm Uthman bint Sufyan, or Abu Sufyan, was a companion, and she was among the women who gave the pledge of allegiance, as Ibn Abdul-Barr said. The Hafiz said in Taqrib, "She is a slave woman who bore a child to Shayba bin Uthman. She was a companion and has a hadith to her credit."He said in Talkhis (2/261), "Its isnad is hasan. Abu Hatim strengthened it in Ilal (834), and so did Bukhari in Tarikh (6/46). Ibn Qattan criticized it, but Ibn Mawwaq responded to him and was correct." End quote. That is, he criticized it because of Umm Uthman bint Sufyan, saying, "Her status is not known." Likewise the Hafiz graded it hasan and did not grade it sahih, and I do not know his reason for that, since all its narrators are trustworthy.As for the second isnad in Abu Dawud, it is what he narrated through the route of Ibn Jurayj, who said, "It has reached me concerning Safiya bint Shayba bin Uthman, that she said" (then he mentioned the isnad). There is a break in the chain between Ibn Jurayj and Safiya bint Shayba. Bayhaqi gave the false impression, by citing this isnad in Kubra, that Abu Dawud narrated it only through this route.Similar in meaning is what was narrated from Ali, who said, "The Messenger of Allah ﷺ forbade a woman from shaving her head." Tirmidhi (914) narrated it from Muhammad bin Musa Jurashi Basri, who said, Abu Dawud Tayalisi told us, Hammam told us, from Qatada, from Khilas bin Amr, from Ali, and he mentioned it. He said, Muhammad bin Bashshar also told us, Abu Dawud told us, from Hammam, from Khilas, similarly, but he did not mention in it "from Ali."Tirmidhi said, "The hadith of Ali contains inconsistency (idtirab). This hadith was also narrated from Hammad bin Salama, from Qatada, from Ayesha, that the Prophet ﷺ forbade a woman from shaving her head. The practice among the scholars is based on this. They do not hold that a woman should shave her head, but rather that she should trim it." End quote.I say, as for the hadith of Ayesha, Bazzar narrated it in Kashf Astar (1137), and it contains Mualla bin Abdul-Rahman Wasiti. Bazzar said, "He is not corroborated in his hadith." Haythami mentioned it in Majma (3/263), saying, after attributing it to Bazzar, "It contains Mualla bin Abdul-Rahman, who admitted to fabrication." Ibn Adi said, "I hope he is fine."Similar in meaning also is what was narrated from Uthman, who said, "The Messenger of Allah ﷺ forbade a woman from shaving her head." Bazzar narrated it in Kashf Astar (1136) through the route of Rawh bin Ata bin Abu Maymuna, who said, My father told me, from Wahb bin Umayr, who said, I heard Uthman say (then he mentioned it). Bazzar said, "We do not know that Wahb narrated anything other than this, and no one narrated from him except Ata, and Rawh is not strong." Haythami cited it in Majma al-Zawaid (3/263) after attributing it to Bazzar, "It contains Rawh bin Ata, who is daif."Ibn Munzir said, "They agreed that there is no shaving obligatory on women, rather they only need to trim their hair." They said, "Shaving is disliked for them, because it is an innovation in their case and involves disfigurement." However, if a woman were to shave, it would suffice for her, though she would be doing wrong, and the prohibition is to be understood as a matter of preference rather than strict prohibition.Ayesha said, "We used to perform Hajj and Umrah, and we would not do more than trim about the length of a finger."From Ibn Umar, he said regarding a woman in the state of ihram, "She takes from her hair the length of the index finger."From Ata, he said, "She takes from the surface of her head."These reports were mentioned by Bayhaqi in Kubra.