Yahya related to me from Malik from Ibn Shihab from Salim ibnAbdullah that Abdullah ibn Umar said, "Some one who is detained bysickness before he has got to the House cannot leave ihram until hehas done tawaf of the House and say between Safa and Marwa."
USC-MSA web (English) reference: Book 20, Hadith 104
Arabic reference: Book 20, Hadith 806