Low Birth Weight

Low Birth Weight in United States

United States

Low birth weight infants (weighing less than 2,500 grams at birth) are at increased risk of a number of short- and long-term complications. Low birth weight and preterm birth are leading causes of infant mortality. There are two categories of low birth weight infants: moderately low birth weight infants (between 1,500 and 2,499 grams at birth) and very low birth weight infants (less than 1,500 grams at birth). 

Low birth weight infants are more susceptible to health problems, including heart problems, breathing problems, bleeding in the brain, intestinal disorders and retinopathy, which affects eye development. They are also more likely to develop certain health conditions later in life, such as Type 2 diabetes, heart disease, high blood pressure, obesity, cerebral palsy and learning and behavioral problems.

The average hospital cost is estimated to be $27,200 for a low birth weight infant and $76,700 for a very low birth weight infant, compared with an average hospital cost of $3,200. Very low birth weight infant care accounts for 30% of all newborn health care costs, with an annual cost of approximately $13.4 billion in neonatal intensive care unit hospitalizations. Low birth weight and very low birth weight infants who survive to adulthood often experience serious physical and mental morbidities, significantly increasing the costs of hospitalization throughout their lifespan.

The most common causes of low birth weight are premature birth (earlier than 37 weeks gestation) and restricted fetal growth. During the pandemic, pregnant women who contracted COVID-19 had a higher risk of delivering a premature infant. 

According to America’s Health Rankings data, the prevalence of low birth weight is higher among:

• Non-Hispanic Black women, who have a prevalence twice that of non-Hispanic white women.
• Teenagers and women ages 40 and older compared with women ages 20-39.
• Women who have less than a high school education compared with women who have a college degree; the prevalence of low birth weight decreases with each increase in education level.

Additional studies have found that low birth weight is more common among:

• Women receiving inadequate prenatal care compared with women receiving adequate prenatal care. Prenatal care can help identify health risks and steps that are needed to improve a woman’s health prior to giving birth. 
• Women who smoke or drink alcohol during pregnancy.
• Women with medical risk factors such as chronic health conditions, infections, certain medications, placental problems, history of preterm birth, not gaining enough weight during pregnancy and being pregnant with multiples (e.g., twins or triplets).

Improving women’s health prior to pregnancy may be more beneficial than interventions during pregnancy. Strategies to prevent low birth weight include:

• Focusing on women’s long-term health before and beyond prenatal care (e.g., expanding women’s access to medical and dental services).
• Promoting smoking prevention and cessation programs. 
• Ensuring that pregnant women are able to obtain adequate nutrition. 
• Addressing factors related to demographic, social and environmental risks. 

According to the American Public Health Association, effective tools for reducing disparities in low birth weight include “educating the public and health care providers, broadening access to quality health care services, promoting healthier physical and social environments, supporting innovative research and advocating for efforts to address racial and social inequalities.”

Healthy People 2030 has several objectives related to pregnancy and childbirth, including:

• Reducing preterm births.
• Reducing infant mortality.

Committee to Study the Prevention of Low Birthweight, Division of Health Promotion and Disease Prevention, and Institute of Medicine. Preventing Low Birthweight. Washington, D.C.: National Academies Press, 1985. https://www.ncbi.nlm.nih.gov/books/NBK214456/.

Glass, Hannah, Andrew Costarino, Stephen Stayer, Claire Brett, Franklyn Cladis, and Peter Davis. “Outcomes for Extremely Premature Infants.” Anesthesia & Analgesia 120, no. 6 (June 2015): 1337–51. https://doi.org/10.1213/ANE.0000000000000705.

Johnson, Tricia J., Aloka L. Patel, Briana Jegier, Janet L. Engstrom, and Paula Meier. “Cost of Morbidities in Very Low Birth Weight Infants.” Journal of Pediatrics 162, no. 2 (February 2013): 243-49 e1. https://doi.org/10.1016/j.jpeds.2012.07.013.

Kowlessar, Niranjana M., H. Joanna Jiang, and Claudia Steiner. “Hospital Stays for Newborns, 2011.” HCUP Statistical Brief #163. Rockville, MD: Agency for Healthcare Research and Quality, October 2013. https://pubmed.ncbi.nlm.nih.gov/24308074/.

Petrou, Stavros, Tracey Sach, and Leslie Davidson. “The Long-Term Costs of Preterm Birth and Low Birth Weight: Results of a Systematic Review.” Child: Care, Health and Development 27, no. 2 (March 2001): 97–115. https://doi.org/10.1046/j.1365-2214.2001.00203.x.

Shore, Rima, and Barbara Shore. “Kids Count Indicator Brief: Preventing Low Birthweight.” Baltimore, MD: The Annie E. Casey Foundation, July 2009. https://www.aecf.org/resources/kids-count-indicator-brief-preventing-low-birthweight.

Squarza, Chiara, Odoardo Picciolini, Laura Gardon, Maria L. Giannì, Alessandra Murru, Silvana Gangi, Ivan Cortinovis, Silvano Milani, and Fabio Mosca. “Learning Disabilities in Extremely Low Birth Weight Children and Neurodevelopmental Profiles at Preschool Age.” Frontiers in Psychology 7 (June 28, 2016). https://doi.org/10.3389/fpsyg.2016.00998.

Thorsen, Maggie L., Andreas Thorsen, and Ronald McGarvey. “Operational Efficiency, Patient Composition and Regional Context of U.S. Health Centers: Associations with Access to Early Prenatal Care and Low Birth Weight.” Social Science & Medicine 226 (April 2019): 143–52. https://doi.org/10.1016/j.socscimed.2019.02.043.

Wang, Fu, Yingxiao Hua, Paul K. Whelton, Tao Zhang, Camilo Alonso Fernandez, Huijie Zhang, Lydia Bazzano, Jiang He, Wei Chen, and Shengxu Li. “Relationship Between Birth Weight and the Double Product in Childhood, Adolescence, and Adulthood (from the Bogalusa Heart Study).” American Journal of Cardiology 120, no. 6 (September 15, 2017): 1016–19. https://doi.org/10.1016/j.amjcard.2017.06.037.

Woodworth, Kate R., Emily O’Malley Olsen, Varsha Neelam, Elizabeth L. Lewis, Romeo R. Galang, Titilope Oduyebo, Kathryn Aveni, et al. “Birth and Infant Outcomes Following Laboratory-Confirmed SARS-CoV-2 Infection in Pregnancy — SET-NET, 16 Jurisdictions, March 29–October 14, 2020.” MMWR. Morbidity and Mortality Weekly Report 69, no. 44 (November 6, 2020): 1635–40. https://doi.org/10.15585/mmwr.mm6944e2.