What should a woman do if she makes intention for fasting but menstruates within the day?

Women do not perform prayer or observe fasting during menstruation (haidh) and post natal period (nifas). They perform qada for unobserved fasts later.

If a woman starts fasting, but then menstruates within the day, she breaks her fast, and performs qada for this day after the end of menstruation (Marghinani, al-Hidayah, II, 276). It is not appropriate for her to pretend as fasting until iftar time. Yet, it is more appropriate for her not to eat and drink near others out of respect to the spirit of Ramadan.

Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS,

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