VBAC Uterine Rupture Risk: What 0.5% Really Means

Ask anyone considering a VBAC what scares them most, and the answer is almost always the same: uterine rupture. It's a serious complication, and it deserves to be taken seriously. But the way it gets discussed online — often without any actual numbers attached — makes it sound far more common than it is.

Let's look at what the statistic actually says.

The Number: 0.5% to 0.9%

For a woman with one prior low-transverse c-section (the most common incision type), the risk of uterine rupture during a VBAC attempt is approximately 0.5% to 0.9%, according to data cited by ACOG and multiple large cohort studies.

Turned around, that means somewhere between 99.1% and 99.5% of women attempting a VBAC under these circumstances do not experience a uterine rupture.

Why the Number Feels Scarier Than It Is

A few things make this statistic feel bigger than it is:

Rare events get more attention. A 1-in-150 event that's genuinely dangerous will always generate more conversation online than the 149 uneventful outcomes that surround it.
"Rupture" sounds catastrophic no matter the size. The word does a lot of emotional work, even though outcomes vary — most cases are managed successfully with prompt intervention, which is exactly why ACOG recommends attempting TOLAC at hospitals equipped for emergency cesarean delivery.
We don't naturally compare it to other risks we already accept. Every mode of delivery, including a repeat scheduled cesarean, carries its own risk profile. None of the options is risk-free — the honest comparison is relative risk, not "risky vs. safe." See VBAC vs. Repeat C-Section: How to Weigh Your Options for that comparison.

What Changes the Risk

The 0.5-0.9% figure applies to the most common, lowest-risk scenario: one prior cesarean with a low-transverse incision. Your personal risk can shift based on:

Number of prior cesareans. Some studies show a modest increase in rupture risk with two or more prior cesareans (estimates as high as 1.8% in one large study), though findings vary between studies.
Type of prior incision. A low-transverse incision carries the lowest risk; other incision types carry meaningfully higher risk and may rule out VBAC entirely.
Interval between pregnancies and other individual factors your provider will review with you — the same kinds of factors covered in 5 Factors That Predict a Successful VBAC.

This is exactly why "what's the general risk" and "what's my risk" are different questions — and why an individualized conversation with your OB matters more than a single statistic from the internet.

The Takeaway

A 0.5-0.9% risk is real, and it's the reason VBAC should be attempted at a hospital prepared for a rapid emergency response — not a reason to assume the outcome will be bad. For most eligible candidates, it's a small risk attached to an attempt that succeeds 60-80% of the time.

If you want a more personalized picture based on your own history, our MFMU VBAC Calculator estimates your individual probability of a successful VBAC using the clinical model many obstetricians reference — a good starting point for a deeper conversation with your provider, not a replacement for one.