What is the requirement for a female slave to become an Umm Walad after having a child by her master?

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For a female slave to become an Umm Walad, three conditions must be met: first, she must conceive a free child from him. If the child conceived is a slave, which occurs if a slave master impregnates his slave, the child is a slave, and the female slave does not become an Umm Walad. Similarly, if a Mukatab (a slave contracted for freedom) impregnates his female slave, the child is a slave, and the slave does not become an Umm Walad because the Mukatab is not free. Second, conception must occur while she is in his ownership, whether the intercourse was permissible or forbidden (such as during menstruation, fasting, Ihram, or Zihar). Third, she must give birth to something displaying some feature of a human creation, whether a head, hand, or foot, or even a mere outline, whether the fetus is born alive or dead, or whether it is a miscarriage or a full-term birth. Omar ibn Al-Khattab ruled that if a slave woman delivers from her master, she is freed even if it is a miscarriage, provided some creation is apparent.