What is the ruling on fasting before ovulation and for two days when blood pressure is high, and what is the ruling on using an IUD or other means to prevent pregnancy, and what is the legitimate means?

The blood that the questioner saw before the miscarriage in its second month is not considered menstruation, because, according to the preponderant opinion, a pregnant woman does not menstruate. The blood she saw after the miscarriage is also not considered nifas (definition) (postpartum bleeding), because nifas occurs when the form of the fetus becomes apparent, and the minimum period for that is usually eighty-one days. Therefore, this blood is istihadha (irregular bleeding) which does not prevent prayer or fasting. She must make up the days she missed fasting.