In the past, doctors said 'once a cesarean always a cesarean'. However, over the last decades more doctors encouraged their patients to attempt and try for a vaginal birth after cesarean (VBAC), even if they previously had a cesarean delivery. Below are what some of the criteria that increase or decrease chances having a successful VBAC:

Higher Chances for a
successful VBAC
Lower Chances for a
successful VBAC

Your previous cesarean was not done for stalled labor.
You do not have the same condition that led to a previous cesarean (such as a breech, or feet-down, fetus).
You have had a vaginal delivery or a successful VBAC before.
Your labor starts on its own and your cervix dilates well.
You are younger than 35.2
Your chances of a successful VBAC are lower when:2

Your previous cesarean was because of difficult labor, which is called dystocia. This is especially true if you were fully dilated when you had a cesarean section for dystocia.

You are obese.
You are older than 35. 2
Your fetus is very large [estimated as bigger than 9 lb (4082 g)].
You are beyond 40 weeks of pregnancy.
Your last pregnancy was less than 18 months ago.