LOW BIRTH WEIGHT

This indicator reports the total number of low birth weight infants and very low birth weight infants as a proportion of the total number of births. Low birth weight is defined as infants born weighing less than 2,500 grams (5 pounds, 8 ounces). Very low birth weight infants are defined as a subset of low birth weight infants born weighing less than 1,500 grams (3 pounds, 5 ounces).

Low birth weight infants have an increased risk of experiencing developmental problems and delays. In addition, these infants are at higher risk for serious illness, disability, lifelong health difficulties and are more likely to die before their first birthday.1 Amongst very low birth weight infants, the risks are higher and the negative outcomes more severe, especially the risk of death in the first year – 22% compared to 1% for low birth weight infants.2 The primary causes of low birth weight are premature birth and fetal growth restriction. Risk factors for low birth weight include smoking, alcohol/drug use during pregnancy, multiple births, poor nutrition, maternal age, socioeconomic factors, domestic violence and maternal or fetal infections.

• In 2017, there were 38,173 births to residents in Orange County, of which 5.8% (2,222) were low birth weight infants, a decrease from the high of 6.7% in 2011 (a 13.4% decrease) and the lowest rate recorded since 2005.

• Overall, the Orange County rate is lower than the 2017 rates for California (6.9%)3 and the United States (8.3%)4

• Very low birth weight infants comprised less than 1.0% (329) of the total births.

• When assessed by race/ethnicity, the percent of low birth weight infants within each group were: Black (8.5%), Asian (5.8%), Hispanic (5.8%) and White (5.2%) infants.

Note: N/A is no data available. *Rates based on less than five low birthweight births (less than 2,500 grams) are unstable and therefore should be interpreted with caution.

Health Care Agency, Family Health Division