Preterm Birth

When a baby is born before 37 weeks of pregnancy, the birth is called a preterm birth and the baby is premature. In 2021, almost one of every 10 babies was born prematurely in the United States (CDC, 2022).

In Minnesota, prematurity is the leading cause of infant death, accounting for 31.8% of all infant deaths in the state between 2017-2021. In 2020, 9.1% of all births were considered premature, a slight decrease from the previous year. Also, disparities by race and ethnicity still exist. For instance, between 2016-2020, American Indian (13.7%) and African american/Black (9.9%) women had higher rates of premature births than Non-Hispanic white women (8.6%).

Risk Factors for Preterm Birth

Babies born premature may be at greater risk of experiencing lifelong health problems. For example, some may develop illnesses that affect their breathing, feeding and digestive problems, cerebral palsy, intellectual and/or developmental delays that lead to challenges in school and much more. The causes of preterm birth are not fully understood. However, risk factors related to medical, personal/lifestyle, or environmental exposures may increase the chance of babies born too early. The list below contains medical, lifestyle/personal, and environmental risk factors related to preterm births.

Medical Related Factors

• Personal or family history of premature birth.
• Preterm premature rupture of membranes.
• Preterm labor.
• Short cervix.
• Uterine infection.
• Sexually transmitted infections.
• High blood pressure.
• Diabetes.
• Obesity.
• Being underweight or overweight before pregnancy or not gaining enough weight during pregnancy.
• Carrying twins or multiples.

Lifestyle/Personal Factors

• Commercial tobacco product use including exposure to second hand smoke.
• Substance use, including alcohol use.
• Intimate Partner Violence.
• Stress.
• Close pregnancy spacing (less than 18 months between pregnancies).
• Delayed prenatal care.
• Early elective delivery.
• Poverty or low socioeconomic status.
• Racism.
• Young or advanced maternal age (women under 17 and over 35 years of age).

Environmental Factors

• Exposure to pollutants: Chemicals in the air, water, or in personal care products such as phthalates, Bisphenol-A (BPA), flame retardants, air pollution, or lead.

Impact of Preterm Births

Preterm births may affect the long-term health of babies and the wellbeing of parents, families, and communities.

To learn more about the impact of preterm births on babies, parents, and families, visit:

• CDC: Premature Birth
• March of Dimes: Premature babies
• March of Dimes: Report Card
• ACOG: Preterm Labor and Births FAQs
• AAP HealthyChildren.org: Common Parent Reactions to the NICU