Reference: Fataawa Ramadhaan – Volume 2, Page 592, Fatwa No.578
al-Muntaqaa – Volume 1, Page 34
Question: The questioner says she had an operation on her throat and the doctor advised her not to fast the month of Ramadhaan. So is she required to make an expiation or [just] make up [the missed fasts]?
Response: She is required to make up the days she did not fast, as Allaah (Subhaanahu wa Ta’aala) says:
{…and whoever is ill or on a journey, the same number [of days which one did not observe fasts must be made up] from other days}, Soorah al-Baqarah, Aayah 185
And it was because of this illness (operation) that she had not fasted, so she must make up the [fast for the] days she had not fasted.