ANSWER:

Once the prayer time is due and she cleans herself and makes Wudhu, she can remain with this wudhu until the time is over.

It is best to pray at the beginning of the time with the minimum amount of impurity possible.

A woman has Istiadha (colored discharges) & prayer time starts so she washes herselfs & does Wudu. Must she pray immediately after doing that or could she pray the prayer at a later time because of work (but still in the correct time). Like she cleans herself & does Wudu at the beginning of Dhuhr time but she prays the prayer in the middle or close to the end of Dhuhr time without cleaning again?