by EBSCO Medical Review Board

Preterm labor is labor that starts before the 37th week of pregnancy. A full-term pregnancy lasts 38 to 42 weeks.

Fetus at 24 Weeks
nucleus image
Copyright © Nucleus Medical Media, Inc.

It may be able to stop this problem with medicine and rest. Corticosteroids may also be given to help the baby's lungs grow.

Babies born before 37 weeks are premature. Babies born too early are at higher risk problems like:

  • Low birth weight
  • Problems breathing
  • Developmental problems
  • Learning disabilities
  • Problems seeing
  • Intestinal problems
  • Seizures
  • Cerebral palsy
  • A buildup of fluid in the brain
  • Bleeding in the brain
  • Sudden infant death syndrome (SIDS)

The cause of preterm labor is not always known. Sometimes it is caused by preterm premature rupture of membranes (PPROM). This is when the amniotic sac breaks before 37 weeks and labor has not started within 1 hour.

What are the risk factors for preterm labor and delivery?What are the symptoms of preterm labor?How is preterm labor diagnosed?What are the treatments for preterm labor?Are there screening tests for preterm labor?How can I reduce my risk of preterm labor and delivery?What questions should I ask my doctor?Where can I get more information about preterm labor and delivery?


American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 171: Management of Preterm Labor. Obstet Gynecol. 2016 Oct;128(4):e155-64, reaffirmed 2018.

Preterm labor. EBSCO DynaMed website. Available at: . Accessed July 30, 2020.

Preterm labor and birth. The American College of Obstetricians and Gynecologists website. Available at: Accessed July 30, 2020.

Preterm labor and birth: overview. National Institute of Child Health and Human Development website. Available at: Accessed July 30, 2020.

Revision Information