When is a Braxton-Hicks contraction actually preterm labor?

Braxton Hicks contractions that are increasing in frequency, intensity or duration, are developing a rhythmic pattern or are becoming painful are all indicators of preterm labor. In addition feelings of vaginal heaviness or increased vaginal discharge often are early indicators of preterm labor.

Braxton-Hicks contractions are the tightening of your uterine muscles that usually last around 30 seconds. (Actual labor contractions usually last 30-90 seconds.) They should go away when you change positions, either from sitting to standing or vice versa. If they do not go away, happen more than 4 times in an hour, or are accompanied by changes in vaginal discharge, you should go to a doctor. These are signs of preterm labor.