The following graphs represent the percentage of births that receive adequate, intermediate or inadequate prenatal care.  The level of care is measured using the Kessner Index which is a classification of prenatal care based on the month of pregnancy in which prenatal care was begun, the number of prenatal visits and the length of pregnancy.  An initial first visit to the doctor after the first three months of pregnancy is considered too late for adequate care.  The optimum number of visits for adequate care is 16 visits.