For how long should a woman who miscarried in her second month and has been bleeding for a long time abstain from prayer, and is she considered like a pregnant woman or like a menstruating woman, and how should she perform her prayers?

The blood resulting from a miscarriage in the second month is considered istihada (non-menstrual vaginal bleeding), not nifas (definition) (postnatal bleeding), because the creation of a human being is not yet apparent in it. This only becomes apparent after more than eighty days have passed.

The woman must take precautions and perform ablution (wudu') for each prayer after its time has begun. She should perform both obligatory (fard) and supererogatory (nawafil) prayers. She is subject to the rulings of ritually pure women, except for what coincides with her regular menstrual period, which she should count as menstruation.

If she ceased praying, assuming it was nifas, then according to the majority of scholars, she must make up all the prayers she missed during that period. This is the more cautious approach and clears her of responsibility.