Premature birth

Being born premature is a serious health risk

A full-term pregnancy is 40 weeks of gestation. A premature birth, also called a preterm birth, is one that happens before 37 weeks of completed pregnancy. A very premature birth happens before 32 weeks of completed pregnancy.

Over 5,000 babies a year are born premature in Minnesota. Premature birth is a leading cause of death in the first month of life and contributes to one in three infant deaths. Babies who survive a premature birth face the risk of serious lifelong health problems such as intellectual disabilities, cerebral palsy, breathing and respiratory problems, vision and hearing loss, and feeding and digestive problems. The more premature a baby is, the more severe their health problems are likely to be.

See more information about risk factors for a premature birth at the bottom of this page.


Premature births in MN

 
 
Limited to singleton births. * Change in gestational age definition beginning in 2012. Source: Minnesota Center for Health Statistics. National birth data is not yet available for 2016.

Beginning in 2012, the length of a baby’s gestation is based on the obstetric estimate, sometimes called a physician estimate. Prior to 2012, gestational age was based on last menstrual period. Learn more about how gestation is measured at "How birth outcomes are identified?" on the About the birth outcomes data page for these indicators.

Since 2012, between 6 and a half to 7 percent of babies born in Minnesota each year are premature. Among 2016 singleton births in Minnesota, 6.9 percent were born premature (before 37 weeks), which was about 4,700 babies. Most of these were moderate to late preterm (32-36 weeks).

The proportion of premature births in Minnesota is consistently below the U.S. national average. Among 2015 births, the most recent year of national data, 6.9 percent of Minnesota singleton births were premature, compared to 7.8 percent nationally.


Premature births in Minnesota by mother's race and ethnicity

 
 
Limited to singleton births. Categories are non-Hispanic ethnicity unless noted. Data are for 2012-2016. Source: Minnesota Center for Health Statistics. 

There are racial and ethnic disparities in premature births in Minnesota. A mother is more likely to have a premature birth if she identifies as: American Indian, other or unknown race, African American or black, or Hispanic.


Premature births in Minnesota by mother's age

 
 
Limited to singleton births. Data are for 2012-2016. Source: Minnesota Center for Health Statistics. 

Teens and women over age 40 are more likely to have a premature birth in Minnesota compared to the average rate of prematurity for all Minnesota mothers.


Some women have an increased risk of a premature birth

Sometimes a baby is born premature for no known reason. Many women who have a premature delivery have no known risk factors. Risk factors for premature birth are:

  • Carrying more than one baby (twins, triplets, or more)
  • Having a previous premature birth
  • Problems with the uterus or cervix
  • Chronic health problems in the mother, such as high blood pressure, diabetes, and blood clotting disorders
  • Certain infections during pregnancy
  • Cigarette smoking, alcohol use, or use of illegal drugs during pregnancy
  • Exposure to secondhand smoke

Other possible risk factors:

  • A mother's age, race, and income level:
    • Black or African-American women
    • Teenagers and women older than 35 years
    • Low income
  • Late or no prenatal care
  • Stress
  • Exposure to air pollution
  • Exposure to drinking water contaminated with lead