What comes out is not blood per se, but lochia, post-partum vaginal discharge that contains blood, mucus, and even placental tissue. Lochia starts out as bright red (lasting three to five days), then tapers off to a pink or brown-tinged discharge (six to 10 days), until it finally resolves itself as yellowish or whitish discharge. All women who give birth experience lochia, whether the delivery was vaginal or by caesarean section. Remember to wash your perineal area thoroughly to avoid infection. It will also help to make you feel clean.
Call the doctor: If you detect an offensive smell or if the blood soaks through a large pad every hour.