A woman with premature labor experiences labor before a baby is fully developed inside the womb. Although premature labor can occur at any time during the pregnancy, most cases occur after the 20th week of gestation.

Premature labor occurs in approximately 11 out of every 100 pregnancies.

Warning signs of premature labor include:

• Worsening low back pain
• Muscle cramps in the thighs
• Vaginal discharge
• Vaginal bleeding
• Onset of more than 3 contractions per hour:
• After the 20th week, but before the 37th week of pregnancy