What is the description of the discharges that nullify ablution (Wudu'), what is the ruling on transparent discharges resembling Madhi (pre-seminal fluid), and must the prayer be repeated if the discharges were very scant?

If the discharge is pre-seminal fluid (madhy), it is necessary to purify the body part it touched, sprinkle water on the garment, and perform ablution (wudu') for prayer. If it is from the ordinary vaginal secretions, then it is pure according to the more sound opinion, but it invalidates ablution, whether little or much.

If you are certain that something has exited from the private parts, then ablution is invalidated. However, if there is doubt about its exit, the original state is the continuation of purity. There is no need to repeat prayers unless you are certain that the discharge exited before or during the prayer. If there is doubt about the time of its exit, it should be attributed to the nearest probable time.