VBAC safey research - Mothering Forums
VBAC > VBAC safey research
puzzleRN's Avatar puzzleRN 07:54 PM 02-21-2011

 My SIL had a c-section 9 yrs ago because her son was breech and had a prolapsed cord.  She's had two successful VBAC's and is expecting again this summer (it will be 5 yrs since her last birth).  She keeps talking about how she is super high risk and is worried about uterine rupture so she needs a fancy hospital, etc and I think she's over-reacting a bit.  Does anyone know if the risk of uterine rupture decreases over time?  Any one have good articles/ books that talk about how safe VBAC's actually are?  I've read a few over the years but can't seem to put my finger on anything at the moment.  She's overseas right now but will back in the US for the birth and keeps acting like she'll have trouble finding a doctor that will do the VBAC since she's so "high risk."   Is that really so?  I feel like her reaction might be a bit exaggerated.

I've had my babies with midwives at a birthing center so my experience has been very different.  I don't want to come off too strongly since my view in birthing is a bit different that hers but I also don't want her to have a bad experience and/or be forced into a c-section for some silly reason.


labortrials's Avatar labortrials 10:04 PM 02-21-2011

Whoa.  Someone's making her feel like she's high risk?  After TWO successful VBACs?  That doesn't make sense to me.  I think one of the most compelling books out there is Wagner's "Born In the USA" if she needs research & statistics.

AustinMom's Avatar AustinMom 10:47 PM 02-21-2011

I'm pretty sure the risk of Uterine rupture goes down after VBACs.  Pushed by Jennifer Block is good to.  Maybe contact a local ICAN chapter?  Have her contact one? Go with her to one?  www.ican-online.org is great and I bet they have stuff there.

kltroy's Avatar kltroy 08:48 PM 02-22-2011

I can't find the citation at the moment, but I *know* I've read the stats.  For a first VBAC attempt, the risk is right around 0.5%.  After a successful VBAC, that risk drops to just a bit over 0.1% for subsequent VBACs.  If I come up with the reference for those numbers I will post.  Dont' feel like diging through my stack of liaterature at the moment.

jenniro's Avatar jenniro 08:50 AM 02-23-2011

Your SIL might feel high risk b/c doctors treat VBACs as high risk, like we are going to explode at any moment.  Even though it is not high risk, it is difficult to find a truly supportive provider.  A provider that doesn't just "allow" a trial of labor, but is truly evidence based and supportive of a woman's right to chose her birth.  I am an RN and I wouldn't have believed it if I hadn't been through it, but OBs push scare tactics, outdated info, and sometimes blatantly false info at women that want to VBAC.  Sometimes, they will say "yea, great, lets do a VBAC," and then when you are 38 weeks, they'll say you aren't showing any signs of progressing so your body just can't do it, your fluid is low, the baby is too big, or any other ridiculous reason they can find to get a repeat c-section.  On top of that, society generally feels like a c-section is the easy way to have a baby, so why would someone want to VBAC anyway.  Clearly, the people that say that have never had to recover from a c-section. 


Anyway, the point of my rant is VBAC is not easy to accomplish.  Unfortunately, a lot of women have to fight for the right to have one.  And even if your SIL is a bit of a drama queen, she will need support and understanding as she tries to find a truly supportive provider. 

dlm194's Avatar dlm194 04:17 PM 02-27-2011

Risk of UR does decrease with increasing number of VBACs:

 Labor Outcomes With Increasing Number of Prior Vaginal Births
After Cesarean Delivery

, Obstet Gynecol 2008;111:285–91

Brian M. Mercer, MD, et al.

OBJECTIVE: To estimate the success rates and risks of an attempted vaginal birth after cesarean delivery
(VBAC) according to the number of prior successful VBACs.


METHODS: From a prospective multicenter registry collected at 19 clinical centers from 1999 to 2002, we
selected women with one or more prior low transverse cesarean deliveries who attempted a VBAC in the
current pregnancy. Outcomes were compared according to the number of prior VBAC attempts subsequent
to the last cesarean delivery.


RESULTS: Among 13,532 women meeting eligibility criteria, VBAC success increased with increasing
number of prior VBACs: 63.3%, 87.6%, 90.9%, 90.6%, and 91.6% for those with 0, 1, 2, 3, and 4 or more
prior VBACs, respectively (P<.001). The rate of uterine rupture decreased after the first successful VBAC
and did not increase thereafter: 0.87%, 0.45%, 0.38%, 0.54%, 0.52% ( P_.03). The risk of uterine dehiscence
and other peripartum complications also declined statistically after the first successful VBAC. No increase in
neonatal morbidities was seen with increasing VBAC number thereafter.


CONCLUSION: Women with prior successful VBAC attempts are at low risk for maternal and neonatal
complications during subsequent VBAC attempts. An increasing number of prior VBACs is associated with a
greater probability of VBAC success, as well as a lower risk of uterine rupture and perinatal complications in
the current pregnancy.