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Low birthweight

Low Birthweight is the percentage of live births where the infant weighed less than 2,500 grams (approximately 5 lbs., 8 oz.).

Measure Tabs


Reason for Ranking

Low birthweight (LBW) represents two factors: maternal exposure to health risks and an infant’s current and future morbidity, as well as premature mortality risk. From the perspective of maternal health outcomes, LBW indicates maternal exposure to health risks in all categories of health factors, including her health behaviors, access to health care, the social and economic environment she inhabits, and environmental risks to which she is exposed. In terms of the infant’s health outcomes, LBW serves as a predictor of premature mortality and/or morbidity over the life course and for potential cognitive development problems.[1]

Measurement Strengths and Limitations

Health risks are greatest for very low birthweight babies but infants born below 2,500 grams also face increased risk of morbidity and premature mortality. Low birthweight is preferred to very low birthweight in the County Health Rankings because it is a more common event, allowing for better data coverage. Although gestational age may be a better measure than low birthweight as it better accounts for a child’s neurological and physical development at birth, gestational age can be difficult to accurately ascertain, whereas birthweight is easily measured and reported.

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