Is a fasting intention valid for a woman who is still menstruating at night if she expects her period to end before dawn?

Summary

A woman who has experienced menstruation and purity, with a regular and consistent monthly habit, may make the fasting intention at night even though her bleeding has not stopped. The condition is that she is certain the blood will stop before the Subuh prayer time begins. The intention is valid once she has completed her habitual days of menstruation. A woman whose habit varies and who does not remember her day count cannot validly make the intention until she has completed the longest number of habitual days.

Written in our own words from the original fatwa — check the source before acting on it.