Is it obligatory for a fiancée who is experiencing istiḥāḍah (non-menstrual vaginal bleeding) to inform her fiancé about her condition before marriage?

Both the suitor and the prospective bride must disclose defects that affect the marriage contract. Istihada (prolonged non-menstrual vaginal bleeding) is considered one of these defects that, according to some scholars, may establish for the husband the option of annulment. You must inform your suitor about your istihada, for whoever fears Allah, He will provide for them a way out.