Since its introduction in 1955, the Pap smear has reduced death from cervical cancer by more than 60 percent. Invented by Dr. Georgios Papanikolaou, the Pap smear is a diagnostic procedure in which a health-care professional swabs a cell sample from the cervix and sends it to a lab to see if any of the cells are malignant. Before the invention of the Pap smear, cervical cancer was one of the leading causes of death for women of childbearing age in the United States. Today, it comes in at number 14 on the list of cancers found in women. Low- and middle-income countries lack adequate cervical cancer screening programs; more than 80 percent of cases worldwide now occur there.