Is it permissible for my wife to feed the poor in lieu of making up for the Ramadan fasts she missed due to pregnancy and breastfeeding, given her fear of repeatedly missing fasts if she becomes pregnant again, or must she make them up, and how should she make up for what she missed?

It is permissible for a pregnant or breastfeeding woman to break her fast in the following Ramadan if she fears harm to herself, and she is only required to make up the missed days (qada'). If she fears harm only for the fetus or the infant, then according to the majority of scholars, she is required to make up the missed days (qada') and pay a fidyah, which is feeding one poor person for each day. The qada' must be hastened and cannot be delayed except for a valid excuse. If she delays the qada' without an excuse until the next Ramadan begins, she must make up the missed days (qada') along with the fidyah. If the breastfeeding woman's fear for herself or her infant persists until the next Ramadan begins, she is only required to make up the missed days (qada').