R' Eliezer says: Two matters are among the lenient [decisions] of Beis Shammai and the stringent [decisions] of Beis Hillel. The blood of a woman who had given birth [and] did not [yet] immerse [in a mikveh]: Beis Shammai say: [It is] like her saliva and her urine. But Beis Hillel say: It generates tumah [both] moist and dry. But [Beis Shammai] concede concerning [a woman] who had given birth in a state of zivah, that [her blood] generates tumah [both] moist and dry.