Overview

A premature birth is a birth that takes place more than three weeks before the baby's estimated due date. In other words, a premature birth is one that occurs before the start of the 37th week of pregnancy.

Premature babies, especially those born very early, often have complicated medical problems. Typically, complications of prematurity vary. But the earlier your baby is born, the higher the risk of complications.

Depending on how early a baby is born, he or she may be:

• Late preterm, born between 34 and 36 completed weeks of pregnancy
• Moderately preterm, born between 32 and 34 weeks of pregnancy
• Very preterm, born at less than 32 weeks of pregnancy
• Extremely preterm, born at or before 25 weeks of pregnancy

Most premature births occur in the late preterm stage.