Friday, July 23, 2010

About Damn Time: Good News for Vaginal Birth After Multiple Cesarean!

FANTASTIC NEWS!!!

The American College of Obstetricians and Gynecologists (ACOG) has finally issued a revision of their 2004 guidelines on Vaginal Birth After Cesarean (VBAC).  [About damn time.]

In the new guidelines, ACOG changes positions on a few key elements.  The position changes of greatest import are the ones providing more flexibility for choosing VBAC even when staff aren't "immediately available" on-site to provide emergency care if needed, and the recognition of patient autonomy (the right of each patient to choose VBAC or repeat c-section for themselves, not have it imposed on them by doctor or hospital bans). 

I leave discussion of those topics to other bloggers and ICAN for now (I may eventually comment too...believe me, I have plenty to say on the subject!). Right now the part I most want to comment on is a REVISION of their policy on Trial Of Labor After Cesarean (TOL or TOLAC) in women with 2 prior cesareans.  Hallelujah

New Guidelines for VBA2C

Here's the summary about VBAC after 2 prior cesareans (VBA2C)  from the new ACOG guidelines:
Women with two previous low transverse cesarean deliveries may be considered candidates for TOLAC.
Previously, in the 2004 guidelines, women with 2 prior cesareans were only considered candidates for a trial of labor if they'd already had a vaginal birth.  Without that, women with more than 1 prior cesarean were supposed to be automatically sectioned for any subsequent children.

But now women with 2 prior cesareans can go for a VBAC, regardless of whether they've had a prior vaginal birth. Yes!!!

This is a cause for major celebration for women like me who have had more than one prior cesarean. Granted,  it doesn't make any difference for me personally, because I had my first VBA2C before the 2004 guidelines went into place. I had my second VBA2C after the guidelines, but because I'd already had a vaginal birth at that point they didn't apply to me.  And since I'm done having children, it's moot for me now as well.

But that's all coincidental timing.....I could easily have been affected, and I never forget that.  Most of the hospitals in my city, while still mostly supportive of VBAC, have stopped attending VBAMC completely.....even the University Hospital that has 24/7 anesthesia and OBs on-site.  If I were having my babies now, I'd be out of luck.

But while this doesn't affect me anymore, I care because of all the women I know who have had to search desperately (and often unsuccessfully) well into their pregnancy to find a care provider who would "let them try" a VBAMC, and who have had to endure scaremongering and egregiously inflated risk estimates from various "caregivers" along the way.

I care because of the good, honorable care providers who have been threatened with losing their privileges because they do support VBAMC, or who have been pressured or harassed out of attending VBAMC.

I care because an ICAN friend of mine had a VBA2C this week only because homebirth midwives in her area continue to support VBAMC (the hospitals in her area do not). Otherwise this friend of mine would now be recovering from yet another operation, all while trying to take care of a newborn and 2 toddlers.

I care because of all the women I know who have had to choose between being forced into repeat surgery they didn't need and an out-of-hospital birth that they may not have been comfortable considering. While homebirth is a reasonable choice and most of the VBAMC moms I've known in recent years have chosen a homebirth because it offers their best chance of success, not all women are comfortable with this option and it shouldn't be their only choice for avoiding surgery.

I care because of the women who have been threatened with Child Protective Services if they dared consider a VBA2C.  (The woman in this article isn't the only one.)

I care because of the women who were told they were almost sure to kill their baby if they dared to try a VBA2C. Like this woman, who was told:
Unless you have an elective cesarean at 38 weeks, the baby and you will die.”  -OB to mother with two prior cesareans  (from My OB Said WHAT?!?)
I care because of all the women with 2 or more prior cesareans who have been coerced or scared into repeat cesareans, despite the many complications multiple repeat cesareans exposes them to (Silver 2006). 

I care because of the women I know who came into the hospital well into labor (sometimes even pushing) but who were strapped down and sectioned anyway, despite their protests, simply because of a history of 2 prior cesareans.  One (a doctor herself) sustained significant internal damage from the surgery, and another was denied pain meds for a while after the cesarean "to teach her a lesson."  Another went on to nearly die from placenta accreta in her next pregnancy.

I care because of the women I know who have been coerced into repeat cesareans and have encountered severe complications in subsequent pregnancies (placental attachment issues, uterine rupture, hysterectomy, and stillbirth). 

The 2004 ACOG guidelines had consequences, sometimes dire ones; we must never forget that, and we must never let ACOG forget that either.

It's great to finally have some acknowledgement (belated though it may be) that VBA2C is a reasonable choice, that it does not carry a big excess of risk, and that women have the RIGHT TO CHOOSE their mode of birth.

But I'm pissed that the ripples from the 2004 guidelines are going to continue to echo for many years to come and I'm pissed as hell that it took so long and so much harm to women and babies before ACOG changed its policy back again.

Bad Science, Birth Politics, and VBAMC

After supporting VBAC after Multiple sections (VBAMC) for years, ACOG backed away from it in their 2004 guidelines. The change was highly political,  as I've written about before. It wasn't based in good science, but rather on birth politics and one small, poorly-done study.

In 1999, Caughey et al. published a study of 134 women with a TOL after 2 prior c-sections, and it found a Uterine Rupture (UR) rate of 3.7%.

It didn't matter that no study on VBAMC before or since has found such high numbers, and it didn't matter that the study only involved 134 women and therefore the small sample size could easily distort the findings, creating the illusion of more severe risk than really was there........in the VBAC-lash climate, this became THE study to go by.

It didn't matter that the study had only 134 TOLs in 12 years, that extremely aggressive prostaglandin and pitocin policies were used at this hospital during those years, and that there were NO ruptures in the spontaneous labor VBA2C group.  No, ACOG decided to ban ALL VBA2C unless there was a prior vaginal birth, based on the data from this one small study.

The backstory here is that many care providers were already backing away from supporting VBACs of any kind.  If they could find any excuse to justify ending yet more trials of labor, they'd take it........and they did.

It's not a coincidence that one of the lead authors of this 1999 study was one of the main authors of the 2004 ACOG revised guidelines. She and the others basically ignored or dismissed all the other studies that found far lower rupture rates and focused only on that one in making the decision to recommend against VBAMC without a prior vaginal birth.

Birth politics, anyone?  With women and babies paying the price.

More Recent and Much Larger VBAMC Studies

Since the 2004 guidelines, two other FAR larger studies have found rupture rates much much lower than the Caughey 1999 study in VBA2C women.

Macones 2005 had a study group of 1,082 women, a far larger study group than the Caughey study.  It found a rupture rate of 1.8%, with 16 of the 19 ruptures found in the induced or augmented groups.  This suggests that the rupture rate could have been even lower. 

The authors didn't state the spontaneous rupture rate in the study but I crunched the numbers myself based on the percentages of induced, augmented, and spontaneous labors given in their data tables.  The spontaneous rupture rate in the VBA2C group was 3 out of about 379 spontaneous labors, or about 0.8%, compared to 16 ruptures out of about 703 induced or augmented labors, or about 2.3%.

Although it's impossible in hindsight to know exactly how many ruptures might have been prevented by avoiding induction and augmentation, it's a good bet that the total rupture rate would have been lower than 1.8%.  Thus, this number may not represent the true rupture risk for spontaneous labor VBA2C.

Landon 2005 had a study group of 975 women, also far larger than the Caughey study, and included a small group of women (n=104) with 3 or 4 prior cesareans in its data pool.  It found a VBAMC rupture rate of 0.9%, and that was with inductions and augmentations.  Therefore, the spontaneous labor rupture rate is probably even lower in that study. [I've asked Dr. Landon for the (unpublished) spontaneous labor rupture rate but unfortunately, so far he has not responded.]

A slightly smaller study, Lin and Raynor 2004, confirms that the rate of rupture is smaller in the spontaneous labor VBAMC group.  The full text of the study notes that there were 523 spontaneous labors in the VBAMC group, and this spontaneous labor group had a 0.8% rupture rate.  There were 2 ruptures in the 73 induced labors for a 2.7% rupture rate.

This is information that is very important.  Really, it's the spontaneous rupture rate that is the MOST important to consider when making a decision about whether to consider VBAMC. Women and their caregivers need to know that the VBAMC rupture rates usually quoted are rates distorted by induction and augmentation and that the true risk is likely much lower with spontaneous labor, as it is with VBA1C.

This is the information not being disclosed in the new ACOG guidelines.  They dance around the induction and augmentation issue, noting that a number of studies have found an increased risk of rupture when a trial of labor was induced, but diluting that by mentioning that some studies have only found increased rupture risk in women without a prior vaginal birth or when prostaglandins are used in conjunction with pitocin. 

However, the bottom line is that the lowest rates for uterine rupture are found in the groups of women with spontaneous labor....no induction, no augmentation....and that this is true also for VBAMC women.

Quoting a VBA2C rupture risk as 0.9 - 1.8% makes it sound like this is the risk even if the labor is spontaneous, and it likely is not.  VBAMC research needs to start differentiating between results for totally spontaneous labors, labors augmented with pitocin, and different types of induced laborsas VBA1C research often does. 

Yes, we need more studies with VBAMC spontaneous labors to confirm these numbers, but many more doctors and women might be willing to consider VBA2C if they understood that the real risk of rupture is more like 0.8% or so if labor is spontaneous. 

Full Text of ACOG's New Guideline on VBAMC

Here is the full text of ACOG's new guideline on VBAC after more than one prior cesarean.  I've substituted their study reference numbers with the author/year for clarity here, and also broken up the information into paragraphs for readibility.  The full citations for these studies are at the end of my blog post, with links to their abstracts. While I don't agree with all of ACOG's conclusions, I include the full section here for the sake of documentation:
More Than One Previous Cesarean Delivery

Studies addressing the risks and benefits of TOLAC in women with more than one cesarean delivery have reported a risk of uterine rupture between 0.9% and 3.7%, but have not reached consistent conclusions regarding how this risk compares with women with only one prior uterine incision (Asakura 1995, Caughey 1999, Landon 2006, Macones 2005, Tahseen 2010).

Two large studies, with sufficient size to control for confounding variables, reported on the risks for women with two previous cesarean deliveries undergoing TOLAC (Landon 2006, Macones 2005). One study found no increased risk of uterine rupture (0.9% versus 0.7%) in women with one versus multiple prior cesarean deliveries (Landon 2006), whereas the other noted a risk of uterine rupture that increased from 0.9% to 1.8% in women with one versus two prior cesarean deliveries (Macones 2005). Both studies reported some increased risk in morbidity among women with more than one prior cesarean delivery, although the absolute magnitude of the difference in these risks was relatively small (eg, 2.1% versus 3.2% composite major morbidity in one study) (Macones 2005).

Additionally, the chance of achieving VBAC appears to be similar for women with one or more than one cesarean delivery. Given the overall data, it is reasonable to consider women with two previous low transverse cesarean deliveries to be candidates for TOLAC, and to counsel them based on the combination of other factors that affect their probability of achieving a successful VBAC.

Data regarding the risk for women undergoing TOLAC with more than two previous cesarean deliveries are limited (Cahill 2010).
What About VBAC After 3 or More Prior Cesareans?

Women who have had more than 2 prior cesareans are no doubt wondering how this all applies to them and whether they will be left out in the cold.  Basically, the new guidelines leave the question open-ended.

In the past, while ACOG guidelines did not exactly advocate for VBAC after 3 or more cesareans, it did not ban them either. The 1994 guidelines stated:
A woman who has had two or more previous cesarean deliveries with lower uterine segment incisions and who wishes to attempt vaginal birth should not be discouraged from doing so in the absence of contraindications.
In other words, it was left up to the judgment of the managing care providers and the birthing mother.

The new 2010 ACOG guidelines state that women with 2 prior cesareans are candidates for a TOLAC but that the data on women with 3 or more prior cesareans are limited.

Unfortunately, it is true that we don't have a lot of data on VBAC in women with 3 or more prior cesareans.  Higher-order VBACs have happened, but rarely in any kind of large, systematic way. Several studies have had small numbers of VBAMC TOLACs, but the sample sizes were not large enough for any real conclusions.

There is only one somewhat substantial study of higher-order VBACs. Miller (1994) had 1,827 TOLs in women with 2 or more cesareans. Of these, there were 241 TOLs in women with 3 or more prior cesareans.

Overall, the rupture rate was found to be 1.7% in all VBAMCs combined; 1.8% in VBA2Cs, but only 1.2% in VBA3+Cs. This seems to contradict the theory that rupture risk rises linearly as the number of prior incisions rises. However, these labors may just have been managed with more caution (i.e., less induction and augmentation), thus decreasing the risk of rupture. Without more details, we cannot know. But the 1.2% rupture risk in the higher-order VBAC group is within the 0.9-1.8% risk cited for VBA2C in the new guidelines, so it seems logical that higher-order VBACs should not be categorically denied either.

Despite the discouragement of VBAMC, some women are still managing to have higher-order VBACs, although it is harder now than in the past. The highest-order VBAC documented in the medical literature is a VBAC after 5 cesareans (Veridiano 1989). Wood (2001) documented a VBA4C in Australia. There are anecdotal stories on my main website of  VBA3C, VBA4C, even VBA7C births.

A few recent studies are starting to broach the question of higher-order VBACs again.The Landon 2006 study documented 104 TOLs in women with 3 or 4 cesareans, 84 with 3 prior cesareans and 20 with 4 prior cesareans. Cahill (2010) documented 89 TOLs in women with 3 prior cesareans, all with "no cases of composite maternal morbidity" (i.e. no ruptures, bladder or bowel injury, or uterine artery laceration), and a slightly higher success rate than VBA1C cases (79% vs. 75%).

More data (from large, well-designed studies) are urgently needed to properly evaluate the risks in higher-order VBACs, but the data we have so far suggest that a trial of labor should not be ruled out. Furthermore, any consideration of possible uterine rupture risks in higher-order VBACs must also be balanced against the substantial risks of continuing cesareans (Silver 2006), particularly in women who want larger families.

The good news is that the new guidelines, while not endorsing higher-order VBACs, do not rule them out either.  They merely state that more data are needed.  The fact that the guidelines do not outright preclude them leaves the back door open to doctors and midwives willing to attend higher-order VBACs.  This, plus the mini-trend towards more research on VBAMC, suggests that maybe even the front door could open eventually to the possibility of higher-order VBACs.

Concluding Thoughts

Even though I'm thrilled beyond words that ACOG has finally revised its guidelines, my joy is tempered by outrage that those bad-science 2004 guidelines will continue to have ripple effects for many years to come. 

The Macones study (2005) called for a re-evaluation of the ACOG guidelines on VBAMC. The authors wrote:
It seems reasonable to consider VBAC in those with 2 prior cesareans with no prior vaginal delivery, especially if they go into labor spontaneously.
Landon et al. (2006) also called for VBAMC to remain an option:
A requirement that a history of vaginal delivery be present in women with multiple prior cesarean deliveries to be considered candidates for trial of labor seems unwarranted given the apparent level of risk for uterine rupture and adverse outcomes in this population.  Moreover, a comparison of outcomes after trial of labor in women with multiple prior cesarean versus those undergoing elective repeat operation indicates that both options should remain available for eligible women.
Yet it still took four to five more years for ACOG to actually change those guidelines! And during that time, how many more women got forced into repeat cesareans they didn't want or need? 

The SOGC, the Canadian equivalent of ACOG, stayed open to VBA2C on paper, as did some other countries....but the fact is that the climate for VBAMC chilled considerably around the world because ACOG changed its guidelines

How many women have been butchered in the last six years because of ACOG's unscientific response to a study with only 134 participants

How many will continue to be butchered even after the rule change because doctors now have a distorted sense of risk around VBAMC, or because some malpractice insurance companies refuse to cover doctors or hospitals that "allow" VBAMC? 

Many OBs are never going to go back to "allowing" VBAMC on a regular basis. Like breeches, that horse is out of the barn door and it's not coming back, at least not any time real soon.

Thanks to the Caughey 1999 study and the ACOG 2004 guidelines, many docs will stay with a policy of "twice a cesarean, always a cesarean." They know that scheduled cesareans are more convenient schedule-wise and less risky liability-wise anyhow. They're not going to go back anytime soon, even with the new rules.

So while I'm thrilled that ACOG has finally changed their VBA2C rules, I'm still absolutely LIVID that the 2004 rule change (based on bad science and bad birth politics) resulted in so many women being exposed to so much unnecessary risk.  And I'm even MORE livid that this stupid rule change is likely to go on affecting women's choices around the world for a long time to come, despite it having been rescinded. 

However, I'm trying to remember the positive. 

[Deep calming breath.]

This IS a big step in the right direction, after all. It took a big kick in the behind from the NIH VBAC conference this past year to get it going, but at least there is some momentum in the right direction now. Yessss!!!!!

It at least opens the possibility for VBAMC again for those providers who wanted to support it but felt they couldn't go against the ACOG guidelines and the standard of care in their community. Doctors and midwives need to be able to support VBAMC without feeling they are at extra risk legally for doing so.

This new guideline gives women who want a VBAMC a leg to stand on.  If their doctor tells them they cannot have a TOL, they can show the doctor the ACOG guidelines and point out that they have the right to refuse a repeat cesarean and cannot be coerced into one. 

I'm not holding my breath, waiting for a tidal wave of VBAMCs. Doctors largely ignore contradictory evidence when it goes against the way they want to practice. It's all about convenience and perception of risk these days, and I'm not sure how far ACOG rule changes will go towards altering the prevailing obstetric culture of birth.

Rest assured, though, that there ARE docs and midwives who are "allowing" a TOL after 2 or more cesareans anyhow (thank you, Dr. Landon and Dr. Tate!). They are few and far between.....but there are still some out there. And BLESS THEM for standing against the ACOG machine and standing up for what's right!

And good for ACOG and its current leadership for recognizing and trying to resolve some of the harms that were caused from the 2004 guidelines. This ACOG leadership is a refreshing breath of air compared to some past regimes, and by and large, the Committee on Practice Bulletins (aided by Dr. William Grobman and Dr. Jeffrey Ecker) did a good job of balancing difficult policy questions in this new bulletin.

Now I'm waiting to see MORE providers out there, willing to stand up for women's autonomy in decision-making. Take a stand, providers; nearly half of all U.S. hospitals ban VBACs of any kind and the rate is much higher for VBAMC.  It's time to make your voice HEARD.  It will take lots of pressure on the part of both consumers and healthcare providers for the change to happen. Stop letting the majority of the momentum come from consumers and start adding your voices back to the discussion!

Oh, and ACOG, if you truly believe in women's autonomy in making their own decisions (as you insist you do), it's time to start pressuring more hospitals to reduce their preventable primary cesarean rates.  Don't just pay lip-service to the idea of autonomy; true patient autonomy includes more of a voice in all decisions, not just VBAC decisions. That includes making sure women have the choice of vaginal birth in the scenarios that lead to a lot of "elective" primary cesareans (breech babies, big babies, "late" babies, etc.).  If we reduce the primary cesarean rate, then we can reduce the need for VBACs markedly.

ACOG, this was a decent first step; now back it up with further action.

No woman should be forced into surgery if she doesn't want it.  She should consider the pros and cons of all her choices, but she should choose from a place of knowledge, not a place of coercion.  She should receive counseling from her healthcare providers about the risks and benefits of her various options, but ultimately, the choice should be hers. 

At least we finally have some ACOG recommendations to support that, and which recognizes that VBAMC is a reasonable choice after all. 

About damn time.


References:

Veridiano NP. Vaginal delivery after cesarean section. International Journal of Gynaecology and Obstetrics August 1989;29(4):307-11. PMID: 2571531

ACOG Committee Opinion. Vaginal delivery after a previous cesarean birth. #143, October 1994.

Miller DA et al. Vaginal birth after cesarean: a 10-year experience. Obstetrics and Gynecology August 1994;84(2):255-8. PMID: 8041542

Asakura H, Myers SA. More than one previous cesarean delivery: a 5-year experience with 435 patients. Obstet Gynecol 1995;85:924–9.  PMID: 7770261

Caughey AB et al. Rate of uterine rupture during a trial of labor in women with one or two prior cesarean deliveries. American Journal of Obstetrics and Gynecology October 1999;181(4):872-6.  PMID: 10521745

Wood JR, Quinlivan JA, Keirse MJ.  Trial of labour after four Caesarean sections: a case report and literature review.  Aust N Z J Obstet Gynaecol 2001 May;41(2):233-5.  PMID: 11453282

Spaans WA et al. Trial of labour after two or three previous caesarean sections. Eur J Obstet Gynecol Reprod Biol Sept 10, 2003;110(1):16-9.  PMID: 12932864

ACOG Practice Bulletin: Clinical Management Guidelines for Obstetrician-Gynecologists. Vaginal birth after previous cesarean delivery. #54, July 2004.

Lin C and Raynor D. Risk of uterine rupture in labor induction of patients with prior cesarean section: an inner city hospital experience. American Journal of Obstetrics and Gynecology 2004;190:1476-8.  PMID: 15167874

Macones GA et al. Obstetric outcomes in women with two prior cesarean deliveries: is vaginal birth after cesarean delivery a viable option? American Journal of Obstetrics and Gynecology 2005;192:1223-9.  PMID: 15846208

Landon, MB et al. Risk of uterine rupture with a trial of labor in women with multiple and single prior cesarean delivery. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Obstetrics and Gynecology July 2006;108(1):12-20.  PMID: 16816050

Silver RM, Landon MB, Rouse DJ, Leveno KJ, Spong CY, Thom EA, et al. Maternal morbidity associated with multiple repeat cesarean deliveries. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Obstet Gynecol 2006;107:1226–32.  PMID: 16738145

Tahseen S, Griffiths M. Vaginal birth after two caesarean sections (VBAC-2)-a systematic review with meta-analysis of success rate and adverse outcomes of VBAC-2 versus VBAC-1 and repeat (third) caesarean sections. BJOG 2010;117:5–19.  PMID: 19781046

Cahill AG, Tuuli M, Odibo AO, Stamilio DM, Macones GA. Vaginal birth after caesarean for women with three or more prior caesareans: assessing safety and success. BJOG 2010;117:422–7.  PMID: 20374579

ACOG Practice Bulletin: Clinical Management Guidelines for Obstetrician-Gynecologists. Vaginal birth after previous cesarean delivery. #115, August 2010.

13 comments:

Kristen said...

Your post has me hootin' and hollerin' even louder than I was when I first heard the news. Thanks for being such an inspiring force in birth advocacy. And WOW, thanks for your always thorough and insightful analysis of these issues!

Anonymous said...

What great news! I am so happy that I had a doctor or two stand up for me when I was wanting to vba2c in 2008. Great post Kmom!

Vicki (who had the 12lb vba2c and will at some point send you a birth story!)

enjoybirth said...

THANK you for looking at this issue in such depth. Especially VBA2C section. I am passing onto my readers!

AMY said...

I'm glad to hear some good news for VBAMC momma's. I am attempting a VBA3C's in October. I am VERY lucky to literally find the only supportive mid-wife (and the OB over her) in the entire Phoenix Metro area. I will be delivering in a hospital (which won't be very happy about the midwife letting me try it either.)I have done research for the past 7 years and feel all women should be given a trial of labor if they desire it. This is my 2nd VBAC attempt. My 2nd baby ended up being tranverse half way through labor. On the 3rd baby I couldn't find anyone to support me. Wish me luck!

Christa said...

What a great recap! So exciting, but so far to go.

I wouldn't trade my HBA2C experience for anything though.

Anonymous said...

I am a big and beautiful woman planning on having a baby in the next few months. I cannot say how happy I am to find your website. There is so much information - scientific as well as from personal experience. Thank you from this soon to real big momma.

MeesterMama said...

Thanks for going into such detail! I will def refer back to this. I had a VBA2C in 2008, but like you said not without being argued with and told I was going to kill my baby or myself etc. I am glad things have the potential to change!
ICAN Chapter Leader
Katie

Anonymous said...

Thank you for this EXCELLENT review of the literature. It was great to see the chronologic review and a thoughtful commentary.

Encouraged by your thoroughness, I looked at several articles and was a little disappointed that your well-rounded-ness did not go so far as to acknowledge the other side of the VBAMC problem. You convincingly argue that Caughey 1999 was unduly weighted in the 2004 ACOG opinion. You also spotlight great articles that should have had more weighting. I was left with the impression that the dogma of a linear relationship between scar and risk of rupture should be challenged.

However, you neglected to highlight that rupture rate in VBAMC is in fact higher in all studies 3 fold in most. That is not a small detail.
Also, and perhaps more importantly, is the success rate of a VBAMC is suprisingly low. While 60-80% of VBAC attempts result in vaginal delivery, only 40% of VBA2C did the same. I would want to know this before going to complete dilation and then having to undergo section for the 3rd time. It's a harder recovery to recover from both a long labor AND a section compared to just a scheduled section.

While I agree there should be a choice for all women, the choice also needs to be an informed one and the declining odds of success is probably more important than the rare event of clinically significant rupture.

Also, I am confused that you blame the 2004 ACOG opinion on a decline in VBACs. Guise et al in the June 2010 Obstetrics & Gynecology has a great overview that highlights changing VBAC practice over time. There is not much of a change in either direction after 2004 ACOG. Actually, they attribute the downward trend of VBACs to the 1995 ACOG paper (immediately available provider is required for VBAC) and the McMahon NEJM article (Moms fared worse after trial of labor as opposed to scheduled repeat section).You can read the full text at the NEJM site: McMahon MJ, Luther ER, Bowes WA Jr,
Olshan AF. Comparison of a trial of labor with an elective second cesarean section. N Engl J Med 1996. So, if you're going to get mad at one study, maybe pick McMahon's.

I too applaud the ACOG Aug 2010 bulletin. I also wish it had come earlier. It will be interesting to see in followup articles from Guise et al if the trend reverses in the coming years.
-JAT

Well-Rounded Mama said...

JAT, thank you for commenting.

This post was primarily about VBAMC, and the guidelines for that changed with the 2004 guidelines. This is why I focused on them in this article. They were the death knell for VBAMC.

I am indeed familiar with the flawed McMahon study, and I do know that it was the beginning of the overall VBAC-lash.

However, the change in verbage to "immediately available" in the 2004 guidelines for ALL VBACs truly DID have a tremendous impact on VBACs, particularly in small and/or rural hospitals. It was indeed a crucial change, as the VBAC Ban Database on the ICAN site shows. The VBAC-lash was happening before that, certainly, but the "immediately available" language was the death knell for VBAC in many communities. Hopefully the new guidelines will help bring it back as a choice.

As far as whether there is a linear increase in rupture risk with VBAMC, it totally depends on the study you look at. Some studies find an increase in rupture risk (about twice the risk in Macones 2005 or 3x the risk in Miller 1994, for example) and some did not (not statistically different in Landon 2006 and several other smaller studies). It all depends which study you look at.

In my VBAMC summaries on my website (see below), I note that there is probably a small increase in rupture risk in VBAMC but at this point it is difficult to define its true scope. It is likely NOT as high as the Caughey 1999 study, however. Best evidence suggests that whatever the exact scope is, it is still a reasonable choice to consider, especially given the underestimated harms of multiple repeat cesareans.

As for VBAMC success rates, I am at a loss where you are coming up with a 40% success rate, as most VBAMC studies find success rates in the 60-80% acceptable range.

Pruett 1988 is the lowest success rate for VBAMC I can find (45%). However, it had only 55 TOLs, which is hardly decisive. Most large trials find VBAMC success rates around 70% or so. Some have found rates as high as 90%.

Some studies found a slightly lower success rate for VBAMC compared to VBA1C while others did not. Again, it all depends on the study you look at, but most found very acceptable ranges of success. I suggest you do a more thorough look at the literature.

Tahseen and Griffiths 2010 did a meta-analysis of VBA2C studies and found the following: "Women requesting for a trial of vaginal delivery after two caesarean sections should be counselled appropriately considering available data of success rate 71.1%, uterine rupture rate 1.36% and of a comparative maternal morbidity with repeat CS option."
PMID: 19781046

The 2010 ACOG guidelines have this to say (which I quoted in my analysis): "Additionally, the chance of achieving VBAC appears to be similar for women with one or more than one cesarean delivery."

So I would completely NOT agree with you that the VBAMC success is low and a significant discouraging factor. In fact, most studies show quite reasonable success rates. And success rates are even better when induction is not used.

You can read a more complete summary of the VBAMC studies on my website. I have a summary of all the VBAMC studies to 2001 in my first article at: http://www.plus-size-pregnancy.org/CSANDVBAC/vbac_after_2_cs.htm#Table of Studies.

I have a summary of the VBAMC studies from 2001 to 2007 in my second article at: http://www.plus-size-pregnancy.org/CSANDVBAC/NewestVBAMCresearch.htm.

There are several small new studies since then, including the Tahseen and Griffiths meta-analysis mentioned above, and those are listed in the reference section of my blog post above.

VBAMC actually has a quite reasonable chance of success and given the harms of multiple repeat cesareans, is well worth pursuing for most women.

Well-Rounded Mama said...

JAT, thank you for commenting.

This post was primarily about VBAMC, and the guidelines for that changed with the 2004 guidelines. This is why I focused on them in this article. They were the death knell for VBAMC.

I am indeed familiar with the flawed McMahon study, and I do know that it was the beginning of the overall VBAC-lash.

However, the change in verbage to "immediately available" in the 2004 guidelines for ALL VBACs truly DID have a tremendous impact on VBACs, particularly in small and/or rural hospitals. It was indeed a crucial change, as the VBAC Ban Database on the ICAN site shows. The VBAC-lash was happening before that, certainly, but the "immediately available" language was the death knell for VBAC in many communities. Hopefully the new guidelines will help bring it back as a choice.

As far as whether there is a linear increase in rupture risk with VBAMC, it totally depends on the study you look at. Some studies find an increase in rupture risk (about twice the risk in Macones 2005 or 3x the risk in Miller 1994, for example) and some did not (not statistically different in Landon 2006 and several other smaller studies). It all depends which study you look at.

In my VBAMC summaries on my website (see below), I note that there is probably a small increase in rupture risk in VBAMC but at this point it is difficult to define its true scope. It is likely NOT as high as the Caughey 1999 study, however. Best evidence suggests that whatever the exact scope is, it is still a reasonable choice to consider, especially given the underestimated harms of multiple repeat cesareans.

As for VBAMC success rates, I am at a loss where you are coming up with a 40% success rate, as most VBAMC studies find success rates in the 60-80% acceptable range.

Pruett 1988 is the lowest success rate for VBAMC I can find (45%). However, it had only 55 TOLs, which is hardly decisive. Most large trials find VBAMC success rates around 70% or so. Some have found rates as high as 90%.

Some studies found a slightly lower success rate for VBAMC compared to VBA1C while others did not. Again, it all depends on the study you look at, but most found very acceptable ranges of success. I suggest you do a more thorough look at the literature.

Tahseen and Griffiths 2010 did a meta-analysis of VBA2C studies and found the following: "Women requesting for a trial of vaginal delivery after two caesarean sections should be counselled appropriately considering available data of success rate 71.1%, uterine rupture rate 1.36% and of a comparative maternal morbidity with repeat CS option."
PMID: 19781046

The 2010 ACOG guidelines have this to say (which I quoted in my analysis): "Additionally, the chance of achieving VBAC appears to be similar for women with one or more than one cesarean delivery."

So I would completely NOT agree with you that the VBAMC success is low and a significant discouraging factor. In fact, most studies show quite reasonable success rates. And success rates are even better when induction is not used.

You can read a more complete summary of the VBAMC studies on my website. I have a summary of all the VBAMC studies to 2001 in my first article at: http://www.plus-size-pregnancy.org/CSANDVBAC/vbac_after_2_cs.htm#Table of Studies.

I have a summary of the VBAMC studies from 2001 to 2007 in my second article at: http://www.plus-size-pregnancy.org/CSANDVBAC/NewestVBAMCresearch.htm.

There are several small new studies since then, including the Tahseen and Griffiths meta-analysis mentioned above, and those are listed in the reference section of my blog post above.

VBAMC actually has a quite reasonable chance of success and given the harms of multiple repeat cesareans, is well worth pursuing for most women.

Anonymous said...

WRM,
Thank you for your thoughtful reply. You are right. I need to do a bit more reading. Thanks for pointing me in the right direction. You have a great starting point for investigating VBAMC.
I was quoting Pruett (45%) and after reading up a bit more, it does appear that VBAC success does stay about the same in the 60-80% range.
Maybe an explanation for the Guise data remaining relatively stable for VBACs after 2004 despite many small community hospitals banning VBAC is that VBAC-deliveries merely shifted to larger hospitals. It's the only way I can understand both the national data and the ICAN list.
In any case, I'll be sure to keep up on the topic. Thanks again for maintaining this resource.
JAT

Elaine said...

This needs to be a Clarion article. Great job!
Elaine

Laurel said...

YOU, ARE A WOMAN AFTER MY OWN HEART!!!
Thank you for all your efforts, research, tears and anger - I so appreciate. . .and other women will too, eventually. And the docs? . . .mostly a wasted effort, I fear.