Older Posts

Just kicking the can of risk down the road

This is why cesareans should not be casual or performed for the convenience of anyone.  They should be reserved for real medical reasons so that the benefits of having the cesarean outweigh the risks.  And there are real risks to cesareans, but since the ones list below are future risks, they may seem less real.  Per a November 2011 study published in the Journal of Maternal-Fetal and Neonatal Medicine:

If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.

Placenta previa and accreta are nothing to mess around with.  Accreta in particular has a very high maternal mortality rate and many mothers end up having cesarean hysterectomies.   I write more about accreta here.

Many women do not think these complications are applicable to them as they don’t plan on more children after their two cesareans.  But I know many women, and I’m sure you do too, who were not planning on more children, but got pregnant nonetheless.  Unless you or your partner get sterilized or practice abstinence (what fun!), the chance of you getting pregnant is there.

By performing routine scheduled repeat cesareans, we do reduce the risk of uterine rupture in the current pregnancy, but we are also increasing the risks of accreta, previa, maternal death as well as uterine rupture in future pregnancies.  In addition, another large study found

[t]he risks of placenta accreta, cystotomy [surgical incision of the urinary bladder], bowel injury, ureteral [ureters are muscular ducts that propel urine from the kidneys to the urinary bladder] injury, and ileus [disruption of the normal propulsive gastrointestinal motor activity], the need for postoperative ventilation, intensive care unit admission, hysterectomy, and blood transfusion requiring 4 or more units, and the duration of operative time and hospital stay significantly increased with increasing number of cesarean deliveries.

And this is especially relevant in rural hospitals which institute VBAC bans because they don’t offer 24/7 anesthesia.  Even though the “immediately available” clause was removed in the latest (2010) ACOG VBAC Practice Bulletin, many of these bans still stand.

However, in order to rapidly respond to the potentially sudden diagnosis of accreta, previa, or abruption, the hospital will have to enact many of the same ideas provided at the 2010 NIH VBAC Conference on how a hospital without 24/7 anesthesia can safely offer VBAC and respond to uterine rupture.  So why not just institute those ideas from the get-go and offer VBAC to those who want it?  (I know, I know: medico-legal reasons, which the NIH also addressed, but that is another post.)  From VBAC Ban Rationale is Irrational:

 As David J. Birnbach, M.D., M.P.H (2010), who presented on the impact of anesthesiologists on the incidence of VBAC [at the 2010 NIH VBAC Conference] asserted:

Lack of immediate available of anesthesia may not always be a key factor in outcome [during a uterine rupture], especially in cases where the obstetrician is not present. Many cases of uterine rupture can be stabilized while the anesthesiologists becomes available, and examples have been suggested of ways to reduce the risk associated with such a crisis. These include antepartum [prenatal] consultation of VBAC patients with the anesthesia departments, development of cesarean delivery under local anesthesia protocols, finding methods of improving communication on labor and delivery suites, practice “fire-drills,” and development of protocols matching resources to risk.

I urge you to watch Dr. Birnbach’s presentation along with all the presentations from the 2010 NIH VBAC conference.

Read more about the how the risk of serious complications increase with each cesarean surgery.

Below is Silver’s (2006) study abstract:

J Matern Fetal Neonatal Med. 2011 Nov;24(11):1341-6. Epub 2011 Mar 7.

The effect of cesarean delivery rates on the future incidence of placenta previa, placenta accreta, and maternal mortality.

Solheim KN, Esakoff TF, Little SE, Cheng YW, Sparks TN, Caughey AB. Source Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, CA, USA. Abstract

OBJECTIVE: The overall annual incidence rate of caesarean delivery in the United States has been steadily rising since 1996, reaching 32.9% in 2009. Primary cesareans often lead to repeat cesareans, which may lead to placenta previa and placenta accreta. This study’s goal was to forecast the effect of rising primary and secondary cesarean rates on annual incidence of placenta previa, placenta accreta, and maternal mortality.

METHODS: A decision-analytic model was built using TreeAge Pro software to estimate the future annual incidence of placenta previa, placenta accreta, and maternal mortality using data on national birthing order trends and cesarean and vaginal birth after cesarean rates. Baseline assumptions were derived from the literature, including the likelihood of previa and accreta among women with multiple previous cesarean deliveries.

RESULTS: If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.

CONCLUSIONS: If cesarean rates continue to increase, the annual incidence of placenta previa, placenta accreta, and maternal death will also rise substantially.

http://www.ncbi.nlm.nih.gov/pubmed/21381881

Be Sociable, Share!

2 comments to Just kicking the can of risk down the road

  • Becky

    I think that it is important to give moms all of the information to make their decisions. I know many couples where one partner does get sterilized after their second child. For these moms, who are very certain that they only want two children, ERCS may have fewer risks than TOLAC. Have you seen this study which looked precisely at this issue? It is from 2006 so I am guessing that it is familiar to you: http://www2.cfpc.ca/local/user/files/%7B69BF3871-6121-4430-8B87-EE8D8A86C8AE%7D/VBAC%20Pare.pdf

    • Jen Kamel

      Becky,

      Thanks for your comment! Yes, I am familiar with that study. When I come across any VBAC study, I always wonder if it was included in the 400 page Guise 2010 Evidence Report that was the basis for the 2010 NIH VBAC Conference. Guise 2010 went study by study, measured the strength of each study and assembled an excellent review of the literature to date. Ultimately, this 400 page document was distilled into the 48 page VBAC Final Statement produced by the NIH VBAC Conference. You can get a feel of the topics presented at the NIH VBAC Conference by either reading the Programs & Abstracts document or by actually watching the individual presentations. I was there for the three day conference and it was eye opening. I wish more medical professionals and moms were aware of this information as they are excellent resources for anyone looking to learn more about VBAC.

      Here is an overview of mortality and morbidity per Guise (2010). It’s important to remember that the quality of data relating to perinatal mortality was low to moderate due to the high range of rates reported by the studies included. Guise reports the high end of the range when they discuss perinatal mortality which was 6% for all gestational ages and 2.8% when limited to term studies. This is a long way of saying, we still don’t have a good picture of how many babies die due to uterine rupture.

      It’s also important to remember that these statistics are for all VBACs: all scar types, multiple prior cesareans, induced/augmented labors, etc. It would have been helpful if they had broke out the data in these ways as we know we can reduce the risk of rupture (and perinatal mortality) through spontaneous labor.

      While rare for both TOL and ERCD, maternal mortality was significantly increased for ERCD at 13.4 per 100,000 versus 3.8 per 100,000 for TOL. The rates of maternal hysterectomy, hemorrhage, and transfusions did not differ significantly between TOL and ERCD. The rate of uterine rupture for all women with prior cesarean is 3 per 1,000 and the risk was significantly increased with TOL (4.7 1,000 versus 0.3 1,000 ERCD). Six percent of uterine ruptures were associated with perinatal death. Perinatal mortality was significantly increased for TOL at 1.3 per 1,000 versus 0.5 per 1,000 for ERCD… VBAC is a reasonable and safe choice for the majority of women with prior cesarean. Moreover, there is emerging evidence of serious harms relating to multiple cesareans… The occurrence of maternal and infant mortality for women with prior cesarean is not significantly elevated when compared with national rates overall of mortality in childbirth. The majority of women who have TOL will have a VBAC, and they and their infants will be healthy. However, there is a minority of women who will suffer serious adverse consequences of both TOL and ERCD. While TOL rates have decreased over the last decade, VBAC rates and adverse outcomes have not changed suggesting that the reduction is not reflecting improved patient selection.

      I think it can be summed up in these quotes two, “There is a major misperception that TOLAC [trial of labor after cesarean] is extremely risky” by Mona Lydon-Rochelle MD and “In terms of VBAC, “your risk is really, really quite low” per George Macones MD. Both are obstetricians and researchers. The bottom line is, women are entitled to accurate, honest data. They don’t deserve to have the risks exaggerated by an OB who wishes to coerce them into a repeat cesarean nor do they deserve to have risks sugar-coated or minimized by a midwife or birth advocate who may not understand the risk or whose zealous desire for everyone to VBAC clouds their judgement.

      There are real risks and benefits to VBAC and repeat cesarean and once women have access to good data, they can individually choose which set of risks and benefits they want. I think the links I have provided above represents the best data we have to date.

      Warmly,

      Jen