November is National Prematurity Awareness Month

In 2016, about 1 in 10 babies was born too early in the United States. Learn about the problem, risk factors, and what we can do to reduce premature birth.

About Premature Birth

A developing baby goes through important growth throughout pregnancy—including in the final months and weeks. Premature (also known as preterm) birth is when a baby is born too early, before 37 weeks of pregnancy have been completed. The earlier a baby is born, the higher the risk of death or serious disability. In 2015, preterm birth and low birth weight accounted for about 17% of infant deaths. Babies who survive can have breathing issues, intestinal (digestive) problems, and bleeding in their brains. Long-term problems may include developmental delay (not meeting the developmental milestones for his or her age) and lower performance in school.

Preterm Birth in the United States

Reducing preterm birth is a national public health priority. Preterm birth rates decreased from 2007 to 2014, and CDC research shows the decline in preterm births is partly due to fewer teens and young women giving birth. Despite this success, the preterm birth rate rose for the second straight year in 2016, and about 1 in 10 babies (10%) was born too early in the United States. Additionally, racial and ethnic differences in preterm birth rates remain. For example, in 2016, the rate of preterm birth among non-Hispanic black women (14%) was about 50% higher than the rate of preterm birth among non-Hispanic white women (9%).

Risk Factors

Experts don’t know all the reasons that some babies are born too early. Some things (called risk factors) can increase the chance that a woman will have a preterm birth. However, a woman can still have a premature birth even if she has no known risk factors.
Risk factors for preterm birth include—

• Social characteristics
  • Black race
  • Teens and women over age 35
  • Low socioeconomic position

• Health behaviors
  • Tobacco use
  • Alcohol or drug abuse
• Medical and pregnancy characteristics
  • Mental health (stress, depression)
  • Pregnancy history (short time between pregnancies, delivering a baby preterm in the past, being pregnant with multiples)
  • Pregnancy complications (preeclampsia, placenta previa or placental abruption)
  • Medical disorders (thyroid disease, obesity, asthma, diabetes, high blood pressure)
  • Fertility treatments (assisted reproductive technology or other treatments)
  • Infection within the uterus