Is it permissible for a woman experiencing irregular bleeding (istihada) or continuous transparent discharge to combine prayers generally, or is it restricted to specific cases, such as the difficulty of performing ablution (wudu)?

Continuous secretions that do not stop are considered like istihadah (non-menstrual vaginal bleeding), and require Wudu for every prayer. If this is difficult for her, she may combine Dhuhr and Asr prayers at the time of either of them, and similarly Maghrib and Isha prayers, either by combining them earlier (taqdeem) or later (ta'kheer). The basis for this is the hadith of Aisha (may Allah be pleased with her) regarding the woman with istihadah. Combining prayers is permissible when there is difficulty in performing the prayer at its prescribed time or difficulty in performing Wudu for every prayer. As for the woman with pure secretions, she is not required to tie a cloth ( عصابة ) or renew it, and difficulty is usually absent except in some specific cases.