Postpartum is from Latin, and means after delivery. It's usually used to refer to the period immediately after a woman gives birth to a baby. In earlier times, this was a rather dangerous period during which complications could lead to a woman bleeding to death; ergot used to be used to stop this. Postpartum bleeding is less often fatal today in the "developed" world. More medical attention these days is focused on postpartum mood disorders, which range from "the blues" through postpartum depression to postpartum psychosis. You can find out more about the condition at
http://www.postpartumstress.com/
http://www.depressionafterdelivery.com/