Everyone warns you about the pain of childbirth, but the aches and twinges can linger long after the last moan fades away. After childbirth, your uterus will begin to contract, which is a very good thing if you ever want to stop looking like you swallowed a soccer ball. The process may cause mild to severe cramping, though. It can take from four to six weeks for your uterus to shrink back to its pre-baby size, and the worst of the cramping will probably occur within the first two or three days. Your vagina will also be tender, bruised and swollen, contributing to the discomfort. Having had an episiotomy or experiencing tearing during delivery will require healing time, too. All told, you'll be generally tired, sore and a little flummoxed; this at a time when you were probably looking forward to feeling more like your old self again.