Musnad Ahmad 25:1258

Muhammad ibn Bakr narrated to us, Ibn Jurayj informed us, Abu al-Zubayr informed me that he heard Tawus and Ikrimah, the freed slave of Ibn Abbas, reporting from Ibn Abbas that he said: Duba'ah bint al-Zubayr ibn Abd al-Muttalib came to the Messenger of Allah, may Allah bless him and grant him peace, and said: "O Messenger of Allah, I am a heavy (sickly/weak) woman, and I wish to perform Hajj. How do you command me to enter into the state of Ihram?" He said: "Enter into Ihram and make a condition: 'My place of exiting Ihram is wherever You restrain me.'" He (the narrator) said: So she reached (her destination).