There are pills that will prevent the menses or delay their occurrence. Is it allowed to use such pills during the time of pilgrimage only out of fear of one's menses coming?
It is allowed for a woman to use pills that will prevent her menses during the time of pilgrimage out of fear that her menses may come. But this should be after she has consulted with a specialist who makes certain that her health will be fine. Similarly, she may do the same during Ramadhan if she desires to fast with the people.1
The Standing Committee
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Footnote
1. There seems to be no need for women to go to such lengths. This probably could be considered a kind of overzealousness. There is no real certainty as to the health risks of such pills, like birth control pills. Furthermore, the menses are a natural matter that Allah has ordained for women and there is no need to flee from them. Hence, it must be considered best for women to abstain from such pills since there is no call for them and they cannot be certain of their side effects. Allah knows best.