Overview

Preterm labor occurs when regular contractions result in the opening of your cervix after week 20 and before week 37 of pregnancy.

Preterm labor can result in premature birth. The earlier premature birth happens, the greater the health risks for your baby. Many premature babies (preemies) need special care in the neonatal intensive care unit. Preemies can also have long-term mental and physical disabilities.

The specific cause of preterm labor often isn't clear. Certain risk factors might increase the chance of preterm labor, but preterm labor can also occur in pregnant women with no known risk factors.