Preterm birth is defined as the birth of an infant before 37 completed weeks of gestation (at least 3 weeks before the “due date”). These births are often characterized as either “very preterm” (less than 32 weeks gestation) or “moderately preterm” (32–36 weeks gestation). The outcomes of preterm birth have a dramatic effect on the status of infant health in the United States. A recent review of preterm birth by the Institute of Medicine, a part of the National Academy of Sciences, resulted in publication of Preterm Birth: Causes, Consequences, and Prevention.* The report by this distinguished committee framed the challenge of preventing preterm births.

Being born preterm is the greatest risk factor for infant mortality (death within the first year of life). Recent analyses of infant death data by CDC researchers demonstrate that preterm-related deaths accounted for more than 1/3 of all deaths during the first year of life, and more infants died from preterm causes than from any other cause. (Infant Mortality Statistics from the 2004 Period Linked Birth/Infant Death Data Set ). There are significant racial disparities in preterm birth. African American women have a greater risk of delivering a preterm infant compared to white women.

Women who have experienced one premature birth and are contemplating another pregnancy should discuss this with their physicians. Research from clinical trials has shown promise for useing of a compound containing progesterone to help women prevent additional episodes of preterm labor and delivery.

The reasons for premature births, including preterm labor and delivery, remain unclear. CDC scientists and their partners are collaborating with states, university researchers, and partners in health care to understand why preterm births occur, and what can be done to prevent prematurity.
 

Prematurity
More than a half million babies in the United States—that's 1 in every 8—are born premature each year. Some babies are so small they could fit in the palm of your hand

CDC Preterm Research
CDC is participating in cooperative research with investigators at several universities and the American College of Obstetricians and Gynecologists.

Infant Health Data and Statistics

The Contribution of Preterm Birth to Infant Mortality Rates in the United States

Pregnancy
If you're pregnant or planning to get pregnant, you probably have a lot of questions.  This Web page will help you learn how to be healthy (before, during, and after pregnancy) and give your baby a healthy start to life.

CDC's National Center for Birth Defects and Developmental Disabilities
The National Center on Birth Defects and Developmental Disabilities (NCBDDD) promotes the health of babies, children, and adults, and enhances the potential for full, productive living. 

Preterm Labor and Birth (National Institutes of Health)
This Web site from NIH's National Institute of Child Health and Human Development provides general preterm labor information, and links to clinical trial and research.

The National Library of Medicine (NLM) provides information for health care consumers on preterm births and related topics in maternal and child health.  The NLM Library recently released Go Local for obtaining information on health care services in states and counties throughout the nation.

Preterm Birth* (March of Dimes)
The March of Dimes continues its national campaign to help families and communities cope with prematurity.

First Candle* provides support to families that have experienced the death of an infant through support groups and its hotline.

Recommendations for Preconception Care Source: MMWR 2006;55(RR06):1–23.

Association of State Maternal and Child Health Programs (AMCHP)*
the AMCHP provides leadership on issues affecting the health of women and children. Members include directors of maternal and child health programs, directors of programs for children with special health care needs, adolescent health coordinators, and other public health leaders. Members of this national nonprofit organization also include academic, advocacy and community-based family health professionals, and families.

CityMatch*
A national membership organization of city and county health departments' maternal and child health (MCH) programs and leaders representing urban communities in the United States. 

Maternal Child Health Library at Georgetown University*
Offers a variety of electronic resources, including the MCH Alert, knowledge paths, databases, and other materials developed for health professionals, policymakers, and families. The MCH Library is located at the National Center for Education in Maternal and Child Health at Georgetown University.

Search PubMed for Articles on Infant Mortality
This search is being conducted on PubMed an NLM/NIH service.

Search PubMed for Articles on Infant Health
This search is being conducted on PubMed an NLM/NIH service.

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Page last reviewed: 9/19/07
Page last modified: 9/19/07
Content source: Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion