Question posed to Shaykh Abdullāh Ibn Muhammad Ibn ‘Abdilazīz Ibn Humayd:

The monthly cycle appeared directly after breaking the fast before performing the Maghrib Prayer. Is my fast sound?

Answer:

Yes it is sound. As long as the menses did not come to you until after the setting of the sun, there is no making up of the fast upon you. This day (of fasting) is sound. As for the case if the menses came to you before the Adhaan, meaning by that, before the setting of the sun, the fast for that day has become invalid and it is a must that you make it up. As for the case when the menses has come to you after the setting of the sun and after you have broken your fast, the fast for this day is sound and it is not upon you to make it up, inshā-Allâh.

Source: Question posed to The Noble Scholar Abdullah Ibn Muhammad Ibn Abdil-Azeez Ibn Humayd, former member of the Permanent Committee of Scholars in Saudi Arabia died 1402 Hijri. Taken from: Dars wa-Fatāwā Mukhtārah fis-Siyām, pg. 19-20.

Translated by Abu Yusuf Khaleefah
12th of Ramaḍân, 1437 (06-17-2016)
Masjid Nur Allah, Queens, NYC