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).

Why is this important?

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 birthweight infants, the risks are higher and the negative outcomes more severe, especially the risk of death in the first year with a 22% chance of dying, 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 smoking3, alcohol/ drug use during pregnancy, multiple births, poor nutrition, maternal age, socioeconomic factors, domestic violence and maternal or fetal infections.

• In 2016, there were 38,121 births to residents in Orange County, of which 6.3% (2,397) were low birth weight infants, a decrease from the high of 6.7% in 2011 and the same rate since 2012.

• Overall, the Orange County rate is lower than the 2016 rates for California (6.8%)4 and the United States (8.2%).5

• Very low birth weight infants comprised 1.0% (392) of the total births.

• When assessed by race/ethnicity, the percent of low birth weight infants within each group were: Black (11.0%), Asian (6.8%) Hispanic (6.4%), and White (5.3%) infants.

Note: N/A is no data available.

Woods rate is based on fewer than five births. Rates based on less than five events are unstable and should be interpreted with caution.