Monday, August 19, 2013

Cesarean Wound Complications: A Reason to Avoid CS in Women of Size

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It's no secret that surgery is harder in "obese" people and there is more risk for infection and other wound complications.

This is why doctors generally discourage surgery in fat people.

However, somehow this caution against routine surgery in fat people doesn't seem to apply when it comes to pregnancy, where some care providers routinely just schedule an automatic cesarean section in women with a BMI over 40 (and often under that).

Even when a routine cesarean is not scheduled, research shows clearly that care providers have a lower surgical threshold for "obese" women, and manage labor in this group in a way that leads to more cesareans.

The bottom line here is that cesarean sections in obese women are extremely common, even though the surgery is harder and more risky in this group. And that means many women of size deal with cesarean wound complications. That's a tough way to start motherhood and can interfere with breastfeeding and bonding.

Now, a new study confirms that cesarean wound complications rise as BMI rises. This is not really a surprise, but the study still had lessons to teach the obstetric community ─ if it would just be open to hearing them.

Results of the Study

In the study, the rate of wound complications (infections, wound disruptions) rose in a dose-response relationship to BMI. The wound complication rates were:
  • BMI <30    -            6.6%
  • BMI 30-40 -            9.2%
  • BMI 40-50 -          16.8%
  • BMI 50+    -          22.9%
That means that nearly 1 out of 6 women with a BMI of 40 or more and nearly 1 in 4 women with a BMI of 50 or more developed a significant wound complication.

Not good. But there are studies where the wound complication rate in women of this size is even higher. Alanis 2010 found that nearly 1 in 3 women with a BMI of 50 or more developed cesarean wound complications.

A good reason to stop doing so many cesareans in women of size, right?

Too bad that's not the lesson most care providers will take from this. Many care providers' only answer to the high rate of cesarean wound complications is that obese women need to lose weight before pregnancy. Period.

Never mind that the cesarean rate is outrageously high in obese women and could probably be lowered.  Never mind that many care providers routinely schedule automatic cesareans for women with a high BMI, most of which are questionable.

Never mind that very few "morbidly obese" people lose weight to a so-called normal BMI, let alone maintain that loss for any length of time. Never mind that trying to lose weight yet again often leads to weight cycling, which is a strong risk factor for weight gain in the long run.

And never mind that many of these cesarean wound complications might be preventable with different techniques and protocols more appropriate to these women's size.

Nope, the answer to everything is to tell women to just lose weight, rather than to lower the cesarean rate in obese women or to study how to improve outcome in this group independent of losing weight.

Deep down, some care providers seem to believe that fat women deserve whatever complication happens and don't feel very motivated to study how to improve outcomes in high-BMI women. Others may feel complications are simply a logical consequence of adiposity and not very preventable.

Yet how do they know these outcomes aren't preventable if they don't even study it?

It just stumps me how care providers can have about a 50% c-section rate (or more) in very obese women and have done so little study on how to improve outcomes in this group.

But be that as it may, there are still things to be learned from this study.

Lessons from the Study

Here are a couple of lessons that care providers should be taking from this study.

Lesson #1 - Unless there is a compelling medical reason to use a vertical incision, STOP using it in women of size.

In the study, surgeons did more vertical incisions on women as obesity increased. Yet vertical incisions are associated with increased rates of wound complications and infections in obese women in a number of studies.

It's rarely truly necessary to use a vertical incision, even in extremely obese women, and it increases the risk for poor outcomes. Low transverse incisions have been used successfully even in women of 400-500 pounds without poor outcomes.

If care providers want to lessen wound complications in obese women, then they need stop doing so many vertical incisions. Yet some are still promoting the idea that vertical incisions are the incision of choice in fat people. Wrong.

Lesson #2 - Start studying ways to improve post-cesarean outcomes in women of size. 

Considering that half or more of obese women undergo cesareans in some areas of the U.S. (!!!), why haven't there been studies trying to examine how to reduce complications in these women?

For example, I'd love to see some large randomized trials on optimizing cesarean techniques for women of size, like what dose of antibiotics is best for morbidly obese women. Recent research shows that current antibiotic dosage is not adequate for many high-BMI women but very little research has been done on the efficacy and safety of increasing antibiotic dosage in this group.

Research on other surgical procedures suggests that many obese people benefit from extended antibiotic regimensmore frequent dosing, use of extended-spectrum drugs, and topical infusions of antibiotics during surgery. It may take a combination of increased doses and other techniques to truly bring down the rates of surgical site infections; when will there be research to discover what is the best antibiotic dosage and regimen for "morbidly obese" women who have had a cesarean?

In addition, care providers should study whether changes in surgical technique could improve outcomes in this group. There have been some trials on whether or not to suture the adipose layer and whether or not to use drains, but more research on this is needed to confirm what previous studies seem to show. Currently, the research seems to suggest that there is a strong benefit from suturing the adipose layer, but that surgical drains may do more harm than good. Let's do more research to answer this question definitively.

Closure materials and methods may be relevant as well. The wound complications study we are discussing mentions that more obese women were closed using staples instead of subcuticular stitches, yet some recent research suggests that staples may predispose to more wound complications. Non-absorbable versus absorbable stitches may make a difference, too. Stitching takes longer than staples, especially in heavier women, but doing it (and using optimal materials) might be another way to lower the risk for problems.

Examine wound-healing treatments too, like wound vacs and medicinal honey, to see which ones work the best for speeding surgical healing for those obese women who experience wound complications.

The important thing is to study these options more closely in this population and then develop and implement Best Practice Recommendations for them, instead of just shrugging our shoulders and lamenting the rate of problems.

Lesson #3 - The biggest lesson here is that cesareans should NOT be done without good reason in women of size.  

When are care providers going to study how to lower the cesarean rate in this group?

There are many studies documenting and bemoaning a high c-section rate in obese women. Yet rarely do they study whether this rate can be changed with different management.  

Care providers are not powerless to lower the c-section rate; many studies have shown that cesarean rates can be lowered safely when attention is focused on the problem.  But not one study has been done to try and see if the cesarean rate in obese women could be lowered.

The easiest way to do this would be to stop the common practice of planned cesareans. In one recent study, a third of very obese women had primary cesareans without labor. If one out of every three or four of these women then develop serious wound complications (not to mention the downstream complications of placental issues in future pregnancies), that's a LOT of morbidity resulting from cesareans that are questionable in the first place.

Once you reduce non-labor cesareans, start studying ways to lower the labor cesarean rate in this group. Many care providers believe that a high cesarean rate in labor is inevitable in very fat women, yet studies show very different rates. This suggests that there is room for change.

For example, one study of "super obese" (BMI 50+) women from the U.K. showed half the cesarean rate of a similar group in Kentucky and another group in Canada.

Cesarean rates in "super obese" women are often nearly 50-60% in some areas of North America, yet this U.K. study had a cesarean rate of 30% in women of the same size. This shows that the cesarean rate in labor could be far less in "super obese" women, and is potentially modifiable.

Most very obese women rarely see midwives and this may also be part of why they have high cesarean rates, since hospitals with a high rate of births attended by midwives tend to have lower cesarean rates.  Obese women are induced at very high rates, and this may be a strong part of the cesarean rate in this group as well.

There are many possibilities for trying to lower the cesarean rate in obese women, but at this point, no one is even trying to do so.

If you want to lower the high rate of cesarean wound complications in obese women, the most effective way to do so is to lower the number of cesareans done in this group.


This study shows that cesarean wound complications tend to rise as BMI rises. This is hardly ground-breaking research.

However, it would be far more groundbreaking if researchers turned their attention to proactively preventing more of these complications.

If 1 in 4 (or more) high-BMI women are experiencing significant wound complications, then something needs to change instead of just accepting this occurrence as inevitable.

Unfortunately, most care providers would look at this data and say that it means we need yet another anti-obesity campaign to scare women into losing weight before pregnancy, despite the stacks of evidence showing how difficult and how unlikely this is to happen.

Make no mistake, I'm all for encouraging people to be as healthy as possible, but the data clearly shows that massive, sustained weight loss is very unlikely in most fat people. Putting all your prevention eggs in the weight loss basket means that there will be a lot of egg on the faces of the care providers involved.

Instead, what providers should be doing is recognizing the opportunities that underlie this data.  We don't have to have a 1 in 4 wound complication rate in obese women.  We can change that outcome. Let's start studying how.

The first and most important step, of course, is to stop DOING so many cesareans in women of size.  That includes stopping the all-too-common practice of routine planned cesareans in obese women. It means questioning whether a cesarean in a woman of size is truly indicated on a case-by-case basis, instead of blithely accepting that a high cesarean rate "goes with the territory" in this group. It also means doing large-group research to discover ways to lower the labor cesarean rate in women of size (hint: stop doing so many inductions and expand midwifery access for obese women) and demanding accountability from care providers with extremely c-section high rates in this group.

The second step is to stop doing vertical incisions on obese women unless truly medically needed. This will lower the rate of wound complications and will make postpartum recovery easier, not to mention being less disfiguring to the mother. In addition, stop teaching that vertical incisions are preferable in women of size, when the evidence clearly indicates that they are not. Although most care providers use low transverse incisions in their obese patients, some stubbornly keep doing and even promoting vertical incisions in this group. This takes a big toll on the women who are subjected to them. It's past time for this outdated practice to be retired.

The third step is to research surgical technique and protocols to lessen the risk for wound complications when a cesarean truly is needed in women of size. Study whether surgical drains are helpful or harmful in obese women, research optimal antibiotic dosing and regimens, examine whether closure technique and materials need adjusting, and subject wound healing techniques to closer scrutiny to see which are most optimal in this group.

Although wound healing is always going to be more challenging in obese women, a high rate of cesarean wound complications is not inevitable. Instead of bemoaning the situation, find ways to improve outcomes in this group without having to tie it to unlikely goal of weight reduction.

Bottom line...stop doing so many cesareans on women of size.  And when they are truly needed, have some quality research in place to show how the risk for wound complications can be lessened in this group.


Am J Perinatol. 2013 Jun 13. [Epub ahead of print] Maternal Obesity and Risk of Postcesarean Wound Complications. Conner SN, Verticchio JC, Tuuli MG, Odibo AO, Macones GA, Cahill AG. PMID: 23765707
Objective: To estimate the effect of increasing severity of obesity on postcesarean wound complications and surgical characteristics. 
Study Design: We performed a retrospective cohort study of consecutive cesarean deliveries at a tertiary care facility from 2004 to 2008. Four comparison groups were defined by body mass index (BMI; kg/cm2): < 30 (n = 728), 30 to 39.9 (n = 1,087), 40 to 49.9 (n = 428), or ≥50 (n = 201). The primary outcome was wound complication, defined as wound disruption or infection within 6 weeks postoperatively. Surgical characteristics were compared between groups including administration of preoperative antibiotics, type of skin incision, estimated blood loss (EBL), operative time, and type of skin closure. 
Results: Of the 2,444 women with complete follow-up data, 266 (10.9%) developed a wound complication. Compared with nonobese women (6.6%), increasing BMI was associated with an increased risk of wound complications: BMI 30.0 to 39.9, 9.2%, adjusted odds ratio (aOR) 1.4 (95% confidence interval [CI] 0.99 to 2.0); BMI 40.0 to 49.9, 16.8%, aOR 2.6 (95% CI 1.7 to 3.8); BMI ≥50, 22.9%, aOR 3.0 (95% CI 1.9 to 4.9). Increasing BMI was also associated with increased rates of midline vertical incision, longer operative time, higher EBL, and lower rates of subcuticular skin closure. 
Conclusion: A dose-response relationship exists between increasing BMI and risk of postcesarean wound complications. Increasing obesity also significantly influences operative outcomes.


Anonymous said...

I had a semi-emergent csection with my twins at 38 weeks and pre-eclampsia. Delivery weight about 240. I'm comfortable with that decision--I was not doing well but all resolved with the delivery. Doc had planned a horizontal incision but decided on vertical in the OR due to an unfortunately placed infected ingrown hair and wanting "more room" to maneuver. No post op problems at all. 5 years later I was overdue with a single baby, induction failed x3 attempts and blood pressure going up again. I had no idea there was a difference in outcomes between vertical & horizontal incisions and asked doc to cut along the old scar so as not to have an "anchor" shaped scar. Came home with a post op incision infection. Now I wonder if I should have opted for the anchor...

Cassandra said...

I think high BMI groups get pushed towards csections because obesity is seen as a complication in itself. So if a patient presents with slightly elevated BP, it is taken with the context of obesity as the first symptom of something being wrong with the body. So it's pre-eclampsia, not just a random instance of elevated BP. Gestational diabetes in an obese patient means super sized babies, even if the GD is under control, because there are two factors with the potential to cause a problem, regardless of evidence to the contrary.

I have been unable to find a suitable midwife in the state of Washington, where home birth is covered by insurance by law, because of the midwives voluntarily restricting their client base to women with a lower BMI. Of the remaining options for midwives, they hyperventilate at the first sign of a complication and use phrases like "You HAVE to do X." That doesn't fly with me. I have chosen to give birth in Oregon with the midwives from my first birth because I know they will back off unless there is something seriously wrong. They don't have insurance companies beating them down for any little thing though.

By the way, I had no idea I'm classified as "super obese" until you used it here. And yet I had a wonderful vaginal birth, preparing for my second in 3 months.