Is expiation obligatory upon a woman who caused the miscarriage of her fetus—whose gestational age was 45 days—due to her negligence, and her husband is aware of that?

A pregnant woman cleaning and tidying her home is a natural act and usually does not cause a miscarriage. If a miscarriage does occur as a result, there is no sin upon her. However, if she does something unusual with the intention of causing a miscarriage, and it occurs because of that, then she is sinful, even if it happens before forty days have passed. Yet, there is no blood money (diyah) or expiation (kaffarah) due from her, because the creation of a human being has not yet become apparent in it.