Is the blood that came down considered menstruation or istihadah, and what is the ruling on prayer and marital relations while it is present, and what is the cause of the physical and psychological fatigue, and how can the chances of pregnancy be increased?

If blood returns after an interruption of thirteen days or more, and it continues for a day and a night, then it is menses (hayd). If its duration is less than a day and a night, or it exceeds fifteen days with purity (naqa’), then it is irregular bleeding (istihada). Dark discharges (yellowish or brownish) are considered menses if they are connected to the blood; otherwise, they are not. In the case of irregular bleeding (istihada), intercourse is permissible, and prayer is obligatory after performing ablution for each prayer once its time has entered.