Your Uterus Shrinks
Minutes after your baby's born, your uterus begins to shrink and contract, causing cramps known as afterpains (these are usually comparable to menstrual cramps). Around the same time, you start shedding the uterine lining that thickened during pregnancy. At first, this bloody discharge (called lochia) will be heavy, but as the days go on, it'll gradually get lighter and lighter. You should use sanitary pads during this time: Tampons increase the risk of infection since you're still healing. After six weeks, your uterus will be close to its pre-pregnancy size and the discharge should stop.