All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
It is obligatory for you to make for up the days that you have missed in Ramadan, and it is not sufficient to provide food to the poor. ‘Aa’ishah was authentically reported to have said, “We (women) used to be advised to make up for the fasts but not for the prayers.” She meant the fasts and prayers that women miss during menstruation. If you delay fasting the days that you have missed in Ramadan until the following Ramadan comes, then you are required to feed a poor person for each day that you delayed making up for in addition to fasting that day, unless you have a legitimate excuse for the delay.
Allaah Knows best.