Definition: Percentage of infants born prior to 37 weeks of gestation, based on obstetric estimate of gestational age (e.g., in 2016, 8.6% of infants born to California women were born preterm).
Data Source: California Dept. of Public Health, Birth Statistical Master Files; CDC WONDER, Natality Public-Use Data (Feb. 2019).
Footnote: County-level data reflect the mother's county of residence, not the county in which the birth occurred. Data exclude infants for whom obstetric estimates of gestation were not reported. The notation S refers to data that have been suppressed because there were fewer than 20 preterm births. N/A means that data are not available.
