What should a woman do if haidh begins after she is in Ihraam?

Answer

If haidh begins after entering Ihraam, she only has to desist from entering the Musjid for Tawaaf. She has to remain in Ihraam until purity is attained. She and her mahram will just have to break from the group, delay their departure until she attains purity to enable her to complete the rites of Umrah/Hajj and then be released from Ihraam. While this may entail a financial burden, she will have to arrange a delay until attaining purity.