Does ablution become void by intentionally urinating due to holding urine, knowing that incontinence increases when holding it, and does prayer become invalid when holding back the two impurities (urine and feces)?

It is disliked for a Muslim to pray while suppressing the urge to urinate or defecate, as this diminishes the completeness of devotion (khushu'). The majority of scholars hold that prayer in such a state is valid but disliked.

As for urinary incontinence ( سلس البول), if it is continuous such that the affected person cannot find a time for purification and prayer without urine discharging, then he must perform ablution (wudu') after the time for prayer begins and pray in his condition, and what discharges from him will not harm his prayer.

However, if the urge to urinate (سلس البول الإلحاحي) is such that it stops at a known time, allowing for purification and prayer, then ablution and prayer must be delayed until that time.