It is narrated from Sayyiduna Jabir (may Allah be pleased with him) regarding the hadith of Sayyidah Asma bint Umais (may Allah be pleased with her) that when she experienced postnatal bleeding at Dhu’l-Hulayfah, the Messenger of Allah (peace and blessings be upon him) instructed Sayyiduna Abu Bakr (may Allah be pleased with him) to tell her: “Let her perform ghusl and enter into ihram.”
Hadith Referenceسنن دارمي / من كتاب المناسك / 1843
From both these hadiths, it is established that if a woman sets out with the intention of performing Hajj and she experiences menstruation (hayd) or postnatal bleeding (nifas), then after performing the ritual bath (ghusl), she should enter into the state of ihram and recite the talbiyah, and do everything that the pilgrims do, except that she should not perform the circumambulation (tawaf) of the Sacred House (Bayt Allah al-Haram). As is narrated in the Sahihayn from Sayyidah Aisha radi Allahu anha, she should perform the tawaf of the Sacred House after becoming pure from her days (of menstruation) and performing the ritual bath (ghusl).