April 24, 2014

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    Preterm Birth

Late preterm by maternal age: US, 2009-2011 Average

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• Maternal age is a risk factor for preterm birth, with higher preterm birth rates found among the youngest and oldest mothers in the U.S. 
• During 2009-2011 (average) in the United States, late preterm birth rates were highest for women ages 40 and older (11.6%), followed by women under age 20 (9.2%), ages 30-39 (8.6%) and ages 20-29 (8.1%). 
• Of all infants born during 2009-2011 (average), 9.3% were to mothers under the age of 20, 52.2% were to mothers ages 20-29 years, 35.6% were to mothers ages 30-39 years, and 2.9% were to mothers ages 40 and older. 
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•  Late preterm is between 34 and 36 weeks gestation.
•  National Center for Health Statistics, final natality data.
•  Retrieved April 24, 2014, from www.marchofdimes.com/peristats.

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    Every day 1 in 8 babies in the U.S. is born preterm. Learn how the March of Dimes is funding research and raising awareness.