It is not permissible for a pregnant woman or breastfeeding woman not to fast unless they have an excuse. If they do not fast because they have an excuse, they have to make up for the missed fasts.

When a woman does not fast due to menstruation, she has to make up for the missed fasts. If she cannot fast, she has to feed one poor person for each day.

The one who suffers from epilepsy has to fast in Ramadan, and he is not exempted from fasting because of that. But if he is unconscious for the whole day, then his fast is not valid and he has to make up that day. But if he wakes up during the day then his fast is valid.