With regard to breastfeeding mothers – and also pregnant women – two scenarios may apply:
1 : If the woman is not affected by fasting, and fasting is not too difficult for her, and she does not fear for her child, then she is obliged to fast, and it is not permissible for her not to fast.
2 : If the woman fears for herself or her child because of fasting, and fasting is difficult for her, then she is allowed not to fast, but she has to make up the days that she does not fast. In this situation it is better for her not to fast, and it is makrooh for her to fast. Some of the scholars stated that if she fears for her child, it is obligatory for her not to fast and it is haraam for her to fast.
It is not permissible for a pregnant woman or breastfeeding woman not to fast during the day in Ramadaan unless they have an excuse. If they do not fast because they have an excuse, then they have to make up the missed fasts, because Allaah says concerning one who is sick (interpretation of the meaning):
“and whoever is ill or on a journey, the same number [of days which one did not observe Sawm (fasts) must be made up] from other days”
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