Is the prayer of one who suppressed the urge to defecate before the prayer and did not suppress it during it, or of one who suppressed the urge to defecate during the prayer and did not suppress it before it, accepted?

It is not permissible for a worshipper to begin prayer while restraining stool or urine, due to the Prophet's (peace be upon him) saying: "There is no prayer in the presence of food, nor when restraining the two impurities (stool and urine)." This prevents humility (khushu'). His prayer in this state is valid but incomplete, and he is not required to repeat it. However, if the urge to relieve oneself occurs during prayer after one has already begun, then his prayer is valid and there is no detestability (karaha) as long as it does not prevent him from completing the prayer.