Jabir bin Abdullah (may Allah be pleased with him), concerning the account of Asma' bint Umays (may Allah be pleased with her) when she entered postnatal bleeding at Dhu al-Hulayfah, said that the Prophet (peace and blessings be upon him) commanded Abu Bakr (may Allah be pleased with him): "Tell her to take a ritual bath (ghusl) and enter ihram."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8940