Is it permissible to offer a fidya for a missed day of Ramadan qada' due to a legitimate Shar'i excuse, and is one sinful for performing an act of worship out of precaution?

If a woman menstruates before making up the day she owes from Ramadan, no fidyah (expiatory feeding) is due from her. Some scholars are of the view that if a person was able to make up the fast after Eid al-Fitr, but delayed it until the next Ramadan arrived, or a new excuse arose, then fidyah becomes obligatory upon them, unless they were ignorant of the impermissibility of the delay. According to this view, you would be liable for the expiation of delay if it was possible to make up the fast before the excuse of pregnancy, and you were aware of the impermissibility of delaying. The safer approach here is to pay the fidyah.