Nafi' (may Allah have mercy on him) said that the niece of Sayyidah Safiyyah bint Abi Ubayd (may Allah be pleased with her) began menstruating at Muzdalifah, so she and Sayyidah Safiyyah (may Allah be pleased with her) stayed behind until they reached Mina after sunset on the Day of Sacrifice (Yawm al-Nahr). Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) ordered them to stone the Jamrah whenever they arrived, and he did not consider any expiation due from them both.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9671