Some women who have an abortion either have it before the fetus is formed or even after that. What is the ruling on her fasting on the day during which she had an abortion and what is the ruling on the days during which she sees blood?

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Shaykh Ibn ‘Uthaymeen said: "If the fetus is not yet formed, the blood will not be considered post-partum bleeding. Consequently, she can fast and pray and her fasting is valid. However, if the fetus is formed, the blood would be considered post-partum bleeding and she should not pray or fast. The basic rule for this issue is the formation of the fetus. If it is formed, the blood would be post-partum bleeding and if it is not formed then it would not be considered as such and the rules of each case will be applicable accordingly."

Allaah Knows best.