Menses Ends Before Fajr in Ramadan
What should a woman do if she knows that her menses (Haid) ends before Fajr Prayer in Ramadan? What if she forget the intention of fasting?
In the name of Allah, We praise Him, seek His help and ask for His forgiveness. Whoever Allah guides none can misguide, and whoever He allows to fall astray, none can guide them aright.
If you were certain that your menses had ended and you formed the intention to fast before dawn, even if it was one minute before, then your fast is valid, even if you delayed performing ghusl.
However, if you were uncertain as to whether your period had ended, but you still intended to fast, then the fast was not valid because of your uncertainty as to whether your menses had ended.
Watch this interesting talk to get more information about such ruling with Dr. Muhammad Salah.
Source: Huda Youtube Channel.Soucre Link