Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates from Hafsah (may Allah be pleased with her) that she said: I said: O Messenger of Allah! What is the matter with the people, that they have left the state of ihram while you have not left the state of ihram from your Umrah? He (peace and blessings be upon him) said: "I have matted my hair (talbid) and garlanded my sacrificial animal, so I will not leave the state of ihram until I slaughter it at Mina."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19678