Tawus (may Allah have mercy on him) said: I was with Ibn Abbas (may Allah be pleased with them both) when Zayd bin Thabit (may Allah be pleased with him) said to him: "Do you give the fatwa that a menstruating woman may go back before performing the farewell tawaf?" He said: "Yes!" He said: "Do not give this fatwa." Ibn Abbas (may Allah be pleased with them both) said: "Then go and ask, for my sake, such-and-such Ansari woman whether the Prophet (peace and blessings be upon him) ordered her to do that." He came back laughing and said: "You have spoken the truth."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9759