As for the woman who missed frequent days of obligatory fasting in Ramadan, sheikh `AbdelKhaliqHasan Ash-Shareef, a prominent Azharite scholar, answers,

she has only to count the missed days and make up for them, either successively or at separate days depending on her ability. She can divide them throughout the year or perform them in two years, in accordance with her capability.
There is a difference among scholars concerning paying ransom along with fasting, but I believe that she does not have to pay ransom.