The number of live births with less than adequate prenatal care (3 year average), and the percent of total live births represented. Adequacy of prenatal care is based on the Kessner Index, which measures adequacy by the month the care began, number of prenatal visits and length of the pregnancy. Prenatal care is adequate when it begins in the first trimester and includes, on average, at least one or two additional prenatal care visits per month, depending on the length of gestation.