Definition: Percentage of infants born weighing less than 2,500 grams (approximately 5 lbs, 8 oz). (E.g., in 2022, 7.4% of infants born to California mothers were born at low birthweight.)
Data Source: California Dept. of Public Health, Birth Statistical Master Files (Mar. 2020); CDC WONDER, Natality Data (Mar. 2024).
Footnote: County-level data reflect the mother's county of residence, not the county in which the birth occurred. Data exclude infants for whom birthweight information is missing. For years 2017 and earlier, the notation S refers to numbers and rates that have been suppressed because there were fewer than 20 cases of infants born at low birthweight. For years 2018 and later, the notation S refers to numbers that have been suppressed because there were fewer than 10 cases, rates that have been suppressed because there were fewer than 20 cases, and numbers and rates that have be suppressed because the total county population was lower than 100,000.
