Praise be to Allah.
This issue is the subject of a difference of scholarly opinion. Some scholars are of the view that when half of the night has passed, it is obligatory for her to renew her wudoo’. And it was said that she does not have to renew her wudoo’, and this is more likely to be correct. End quote.
Shaykh Muhammad ibn ‘Uthaymeen (may Allah have mercy on him)