Is expiation obligatory upon my mother who miscarried in the second month of her pregnancy after receiving the cholera vaccine?

First: If a woman took a vaccine while pregnant, unaware of its harm to the fetus, she bears no sin. This is because medical treatment is permissible, and what results from a permissible act is not guaranteed to be free of unintended consequences. The permissibility of taking a vaccine before illness is indicated by the hadith: “Whoever eats seven ‘ajwah dates in the morning, no poison or magic will harm him on that day.” Sheikh Ibn Baz was asked about seeking treatment before the onset of disease, and he answered that it is permissible if there is a fear of its occurrence due to an epidemic or other reasons, in order to ward off affliction. However, wearing amulets and talismans is not permissible.

Second: If a woman intentionally aborts a fetus without a legitimate Shar‘i excuse, she commits a sin and must repent. If the fetus had completed 120 days, she is liable for the diyah (blood money) of the fetus and the kaffarah (expiation). If it was before that, she is not liable for kaffarah.