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Maternal Obesity from All Sides

June 15th, 2011 by avatar

[Editor's note:  In this, our last segment of the Maternal Obesity from All Sides series, Pamela Vireday shares with us some thoughts regarding prevention, and lived experiences of women of size.  To read the series from the beginning, go here Thank you to ALL of our contributors to this important series. Haven't shared this conversation with your social media circle yet?  Take a moment to Tweet it or share it on Facebook!]


Rethinking Prevention and Treatment

Maternity care providers usually consider only 3 ways to improve patient outcomes: weight loss before or between pregnancies, restricting gestational weight gain, or incorporating high-intervention care models.  Let’s look at these approaches first, and then examine some alternatives as well.

Weight Loss Before/Between Pregnancies

The Holy Grail of Prevention in most researchers’ minds is weight loss before or between pregnancies.  But is this wise?

Research strongly supports the idea that significant weight gain before pregnancy increases the risk for complications, leading doctors to focus on the idea of weight loss preventing them. In fact, some research does support weight loss as prevention.  However, this weight loss can come at a price.

Many women of size who lose weight between pregnancies report gaining significantly more in the subsequent pregnancy; 41%  compared to 18% in one study.  Chronic dieters  also tend to have more excessive weight gains in their pregnancies. Furthermore, a history of weight loss or frequent weight cycling is a strong predictor of subsequent large gain outside of pregnancy, and long-term weight loss maintenance is rare.

This is not to say that the weight loss option cannot be discussed with women; some may be desirous of this approach. However, women also have the right to decline it.  An alternative approach may be to choose a “Health at Every Size” program ─ emphasizing healthy habits independent of weight loss status.

Therefore, the potential benefits of weight loss now have to be weighed against its potential to cause more weight gain and complications in the long run.

Prenatal Weight Gain Restriction

More and more, researchers have been focusing on restricting prenatal weight gain in high-BMI women in order to improve outcomes. However, recommendations for optimal prenatal weight gain in this group are hampered by study design issues, lack of uniform definitions of obesity and weight gain categories, and contradictory findings.

Research does suggest that high weight gains are associated with increased rates of cesareans, macrosomia and pre-eclampsia.  However, causal interpretations for this are questionable. Iatrogenic factors influence the cesarean rate because of the fear of macrosomia and lack of blinding about weight gain. And higher weight gain is most likely a side-effect of pre-eclampsia, not a cause of it. Only macrosomia seems closely tied to high weight gain.

Even so, many care providers are now pushing ultra-low gain policies for their obese patients. However, this is not without risk.  Research shows that there are increased rates of adverse outcomes with this approach, including small-for-gestational–age (SGA) infants, prematurity, and perhaps infant mortality.

At this time, the Institute of Medicine recommends a weight gain of 11-20 lbs. for all obese women.  Emerging research suggests that optimal weight gain may differ by class of obesity, but doctors must balance the risks of SGA and prematurity against the risks of macrosomia and cesareans carefully, especially for mid-sized obese women (BMI 30-40).   Placing a pregnant woman into a fat and protein-burning state for maintenance of energy levels may not be the best thing—for mother and fetus, alike.

Furthermore, studies that examine lifestyle interventions in obese pregnant women show mixed results.  Some show reduced gain, while others showed little difference or even increased gain instead.  Many show little difference in birth weight, complications, mode of delivery, or neonatal outcome.  If reduced gain makes little difference in outcomes, why risk it?

Remember, good nutrition should always be the priority over rigid weight gain goals; altering prenatal weight gain through scorched-earth interventions may cause more harm than benefit. And researchers must be careful that focusing on weight gain goals does not encourage punitive practices or overly restrictive advice among clinicians.

Ghettoizing Women of Size

Increasingly, research calls for high-BMI women to be managed as “high-risk” patients.  In practice, this means that obese women are often not considered eligible for low-intervention care models and “alternative” birth choices. Some care providers are even declining to see high-BMI patients at all.

Obese women increasingly report being “ghettoized” into “bariatric obstetrics” practices, unable to access local OBs, midwives, or community hospitals. Many report not being allowed to have a homebirth, birth center birth, waterbirth, or even a VBAC. Many are strongly pressured into a high rate of interventions with few alternatives.

Some providers assume that outcomes will be better with high-intervention protocols across the board, but this has not been proven. While sometimes interventions are needed, anecdotally many women of size find that high-tech care models result in poorer outcomes, more traumatizing births, and more interference with breastfeeding.

Research shows that outcomes are good for other women with midwifery care, even women with “moderate” risk factors.  And since many obese women do have normal pregnancies and births, obese women without serious complications should still be able to choose midwifery care, community hospitals, “alternative” care, and low-tech models of care. To paraphrase Susan Hodges of Citizens For Midwifery, how much perceived ‘risk’ does it take to supercede a mother’s right to patient autonomy?

Other Alternatives for Minimizing Complications

When researchers fixate on weight loss, weight gain restriction, and high-intervention care models as the only methods of preventing problems, they lose the opportunity to explore other sensible avenues of prevention.

The most basic way to improve outcome is to emphasize the importance of a pre-conception check-up to check blood pressure, blood sugar, thyroid function, and prenatal vitamin/folic acid intake. These are vital because the most serious complications in obese women usually come from those with uncontrolled pre-existing conditions.  The importance of good nutrition and exercise for preventing complications should be discussed, but without lecturing and moralizing.

The importance of exercise is perhaps the most potent message for women of size to hear for minimizing complication rates. In one study, the risk for GD in obese women was cut nearly in half by regular exercise. Some studies suggest it may lower the risk for pre-eclampsia as well.  Studies in non-pregnant people show that exercise can improve health greatly, independent of weight loss.

Restrictive dietary advice is controversial.  Many care providers advise obese clients to limit high glycemic-index carbohydrates, but research on this approach is contradictory .  A Cochrane review found some benefits but overall inconclusive results. Since many women of size are insulin-resistant, it seems sensible to encourage complex carbs combined with protein, since this significantly improves glucose and insulin response.  That being said, caution should be taken in implementing a low glycemic index diet; severe carbohydrate restriction can result in a ketogenic state—putting both mother and baby at increased risk.

It has long been speculated that a higher dose of folic acid might lower the risk for birth defects in obese women, and some organizations recommend doing this.  Other resources recommend measuring red blood cell count folate concentration instead and giving additional supplementation only for those with low concentrations.

Some experts have also speculated that supplementation with higher doses of vitamin D before or during pregnancy might help prevent some cases of gestational diabetes, hypertension disorders, and cesareans.  However, research so far has been mixed.

Another preventive option that has been proposed by some organizations is daily low-dose aspirin after the first 12 weeks for those obese women most at risk for pre-eclampsia. Like folic acid and vitamin D, this too needs to be studied further for efficacy and safety but is an intriguing possibility. Because aspirin intake during pregnancy can result in deleterious outcomes in some mother/baby dyads, antenatal aspirin use should only be maintained under the careful guidance of the woman’s maternity care provider.

Care must be taken not to use a too-small BP cuff, which artificially inflates blood pressure readings and can result in over diagnosis of hypertensive disorders. Large arms over 34 cm need a large cuff, and some need a thigh cuff. Care must be taken with forearm readings, as these tend to overestimate blood pressure too.

Anecdotally, many women of size (like all women)  find that avoiding inductions is an important part of improving their outcomes. Indeed, one study of obese women found a c-section rate of 19% with spontaneous labor (vs. 41% for induced labor), and that induction was the start of many complications in this group.   Because induction rates can be as high as 50% in very obese women; avoiding induction may help lower cesarean and complication rates. Adjusting due dates for menstrual cycle length may also help reduce the number of inductions for postdates pregnancies in high-BMI women.

A tincture of patience in labor may be helpful too. Many cesareans occur because of a “failure to wait” among care providers.  Since their first stage of labor tends to be slower and because many care providers opt for cesareans more quickly in obese women, it’s important to allow a truly adequate labor before opting for surgery.

Many high-BMI women report having cesareans for fetal malpositions, and some research supports this.  This suggests that interventions such as manual rotation skills or prophylactic chiropractic care might help lower their rate of cesareans.  Anecdotally, many women of size report that chiropractic care was very helpful in pregnancy and labor.

The fear of big babies is another factor that leads to many inductions and cesareans. Avoiding fetal weight estimations may help avoid harmful interventions and a lower threshold for surgery.

Re-examination of surgical care regimens may also improve outcomes in those who do have cesareans.  For example, many clinicians were taught to use vertical incisions and subcutaneous drains in cesareans in very obese women, yet recent research finds these actually increase the risk of wound complications strongly.  Additionally, a higher dose of antibiotics may be needed in morbidly obese women, and those who develop infections may benefit from extended treatment with more frequent dosing regimens.

However, the most powerful measure for prevention in the pregnancies of women of size is simply having a care provider that does not see them as a ticking time bomb, who understands that large bodies can work “right” too, and who truly believes in their potential to give birth vaginally as well.  Remember the power of the self-fulfilling prophecy; be proactive about complications but expect normalcy.

Conclusion

Weight loss before pregnancy is something that can be considered on an individual basis for those who wish it, but we cannot place all our prevention eggs in one basket.

High-BMI women should probably avoid very high weight gains, but extreme interventions to restrict weight may increase the risk for some adverse outcomes as well and must be viewed with caution.

Forcing all obese women into a high-risk, high-intervention care model penalizes those without complications and may cause more harm than good. Women of size, like all women, deserve the right to patient autonomy and access to care that will improve their outcomes.

Clearly, the pregnancies of high-BMI women carry a higher risk for some complications.  It is important to care about lessening this risk and promoting proactive care. However, we must not let hyperbole about this risk rush us into unwise, ineffective, and even dangerous interventions. We must start examining other options for prevention as well.

Additional References and Links:

Subject Studies and Links
Weight Gain Before or Between Pregnancies and Complications Gethun 2007 http://www.ncbi.nlm.nih.gov/pubmed/17547882 LGA babies 

Villamor 2008 http://www.ncbi.nlm.nih.gov/pubmed/18375499 birth defects

Whiteman 2011 http://www.ncbi.nlm.nih.gov/pubmed/20640971 pre-term births

Paramsothy 2009 http://www.ncbi.nlm.nih.gov/pubmed/19305325 cesareans

Weight Loss and Prevention of  

Pregnancy Complications

Whiteman 2011 http://www.ncbi.nlm.nih.gov/pubmed/21544736 GD 

Glazer 2004 http://www.ncbi.nlm.nih.gov/pubmed/15475723 GD

Getahun 2007 http://www.ncbi.nlm.nih.gov/pubmed/17547882 LGA babies

Paramsothy 2009 http://www.ncbi.nlm.nih.gov/pubmed/19305325 cesareans

Prenatal Weight Gain Restriction in Obese Women Crane 2009 http://www.ncbi.nlm.nih.gov/pubmed/19208280 

Thornton 2009 http://www.ncbi.nlm.nih.gov/pubmed/19585925

Nohr 2008 http://www.ncbi.nlm.nih.gov/pubmed/18541565

Heude 2011 http://www.ncbi.nlm.nih.gov/pubmed/21258962

Riskin-Mashiah 2011 http://www.ncbi.nlm.nih.gov/pubmed/20642383

Low Gestational Weight Gain/Loss and  

Adverse Outcomes in Obese Women

Edwards 1996 http://www.ncbi.nlm.nih.gov/pubmed/8598961 SGA 

Chen 2009 http://www.ncbi.nlm.nih.gov/pubmed/18813025 infant death

Naeye 1979 http://www.ncbi.nlm.nih.gov/pubmed/474659 perinatal mortality

Dietz 2006 http://www.ncbi.nlm.nih.gov/pubmed/16477257 prematurity

Efficacy of Lifestyle Interventions in Obese Pregnant Women Guelinckx 2008  http://www.ncbi.nlm.nih.gov/pubmed/18221480 review of 7 trials 

Mottola 2010 http://www.ncbi.nlm.nih.gov/pubmed/20083959 less gain, no diff birth wt

Shirazian 2010 http://www.ncbi.nlm.nih.gov/pubmed/20013602 less gain, no less complctns

Wolff 2008 http://www.ncbi.nlm.nih.gov/pubmed/18227847 less gain, better glucose mtblsm

Polley 2002 http://www.ncbi.nlm.nih.gov/pubmed/12439652 more gain in ovwt group

Claesson 2008 http://www.ncbi.nlm.nih.gov/pubmed/17970795 less gain, no diff birth wt or CS

Guelinckx 2010 http://www.ajcn.org/content/91/2/373.long RCT, no diff in gain or outcomes

Quinlivan 2011 http://www.ncbi.nlm.nih.gov/pubmed/21466516 less GD, no diff in birth wt

Unequal Access to Lower-Intervention  

Care for Obese Women

Some Ob-Gyns in South Florida Turn Away Overweight Women” 

Midwife Group Won’t Accept Patient with BMI Over 40?”

Fat Mothers To Be Banned From Hospital

In Celebration of the Baby Bump

I Feel Victimized Because I’m Fat

Pregnancy and Doctor Doom – He Was Wrong, Wrong, Wrong!”

Too Fat For a Midwife/Birth Center

Too Fat to VBAC

So Why The BMI Restrictions in Waterbirth?”

Too Fat for a Homebirth VBAC

Too Fat for Vaginal Birth

Big Girth? Then You Can’t Give Birth

Woman Deemed ‘Too Fat’ for Pregnancy

Can They Refuse Me a Waterbirth?”

Experiences of Women of Size in Pregnancy Furber and McGowan 2010 http://www.ncbi.nlm.nih.gov/pubmed/20483513 

Nyman 2008 www.pubmed.gov/19100667

Exercise for Prevention of Pregnancy Complications Dempsey 2004 http://www.ncbi.nlm.nih.gov/pubmed/15533588 

Rudra 2005 http://www.ncbi.nlm.nih.gov/pubmed/16286850

Vitamin D Levels and Complications Ringrose 2011 http://www.ncbi.nlm.nih.gov/pubmed/21631991 hypertension and preg 

Zhang 2008 http://www.ncbi.nlm.nih.gov/pubmed/19015731 GD

Merewood 2009  http://www.ncbi.nlm.nih.gov/pubmed/19106272 CS

Barrett and McElduff 2010 http://www.ncbi.nlm.nih.gov/pubmed/20832734 general review

Lapillonne 2010 http://www.ncbi.nlm.nih.gov/pubmed/19692182 general review

Nutrient Deficiencies and Obesity Schweiger 2010  http://www.ncbi.nlm.nih.gov/pubmed/19876694 

Carlin 2006 http://www.ncbi.nlm.nih.gov/pubmed/16925330

Folic Acid Recommendations and Obesity CMACE/RCOG Joint Guidelines http://www.rcog.org.uk/files/rcog-corp/CMACERCOGJointGuidelineManagementWomenObesityPregnancya.pdf
Blood Pressure Cuff Size Maxwell 1982 http://www.ncbi.nlm.nih.gov/pubmed/6123760 

Graves 2001 http://www.ncbi.nlm.nih.gov/pubmed/11248756

Pierin 2004 http://www.ncbi.nlm.nih.gov/pubmed/15199302

Improving Cesarean Outcomes in  

Obese Women

Ramsey 2005 http://www.ncbi.nlm.nih.gov/pubmed/15863532 

Chelmow 2004 http://www.ncbi.nlm.nih.gov/pubmed/15121573

Bearden and Rodvold 2000 http://www.ncbi.nlm.nih.gov/pubmed/10843460

http://wellroundedmama.blogspot.com/2010/08/antibiotic-underdosing-in-obesity.html

Long-Term Efficacy of  

Weight Loss Programs

Aphramor 2010 http://www.nutritionj.com/content/9/1/30 

Bacon and Aphramor 2011 http://www.nutritionj.com/content/10/1/9

Martin 2008 http://www.ncbi.nlm.nih.gov/pubmed/18787526

Hill 2005 http://www.ncbi.nlm.nih.gov/pubmed/15867898

Jain 2005 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1309653/?tool=pubmed

Sarlio-Lähteenkorva 2000 http://www.ncbi.nlm.nih.gov/pubmed/10702760

Ikeda 2005 http://www.ncbi.nlm.nih.gov/pubmed/16029691

Garner and Wooley 1991 http://psycnet.apa.org/?fa=main.doiLanding&uid=1992-13614-001

Miller 1999 http://www.ncbi.nlm.nih.gov/pubmed/10449014

Wt Loss/Wt Cycling as Risk Factor for Subsequent Weight Gain/High BMI Jeffery 2002 http://www.ncbi.nlm.nih.gov/pubmed/12080451 

Korkeila 1999 http://www.ncbi.nlm.nih.gov/pubmed/10584040

Field 2004 http://www.ncbi.nlm.nih.gov/pubmed/14981219

Exercise for Prevention Sanz 2010 http://www.ncbi.nlm.nih.gov/pubmed/20675173 

Lee 2005 http://jap.physiology.org/content/99/3/1220.abstract

Church 2004 http://care.diabetesjournals.org/content/27/1/83.abstract

Hamer and O’Donovan 2010 http://www.ncbi.nlm.nih.gov/pubmed/19770655

Health At Every Size Bacon 2005 http://www.ncbi.nlm.nih.gov/pubmed/15942543 

http://wellroundedmama.blogspot.com/2008/07/health-at-every-size-paradigm.html

Ernsberger and Koletsky 1999 http://onlinelibrary.wiley.com/doi/10.1111/0022-4537.00114/abstract

 

 

 

 

Maternal Obesity , , , , , , , , , , , , , ,

Maternal Obesity from All Sides

June 7th, 2011 by avatar

[Editor's note:  This is part two of a seven-part series on maternal obesity featuring Kimmelin Hull, UNC-Charlotte Assistant Professor of Kristen Montgomery, childbirth educator and expert blogger on maternal weight issues, Pamela Vireday, from the Well Rounded Mama blog site, and health psychologist, Certified Lactation Consultant (IBCLC) and La Leche League leader,  Kathleen Kendall-Tackett.  To read the first post in this series, go here.]

Complications of Maternal Obesity:  A Closer Look
Let’s examine a few of the individual complications highlighted in yesterday’s post—including their real and purported impact on the perinatal outcome of the mother/fetus(child) dyad, as well as the habitual vs. evidence-based methods for handling these complications in common practice:

Gestational Diabetes
According to Dr. Mahmood’s review, the relative risk ratio of developing GD for an overweight woman is 1.7 compared to her normal weight counterpart.  An obese woman has a 3.6 relative risk of developing GD compared to her normal weight counterpart.  A 2007 meta-anlysis by Chu, et al demonstrated similar results:  odds ratios for developing GD, compared to their normal weight counterparts were 2.14 (overweight), 3.56 (obese) and 8.56 (morbidly obese) (Diabetes Care August 2007 vol. 30 no. 8 2070-2076). The Cochrane Pocket Book –Pregnancy and Childbirth (Cochrane Collaboration and John Wiley & Sons, LTD. pg 92) describes the incidence as affecting between 3 and 6% of pregnancies—that comes out to 30-60/1,000 women.  (Some resources suggest a higher incidence of GD—upwards of 18% of U.S. pregnancies.)

Once a woman has undergone a glucose tolerance test—typically around the 24th – 28th week of gestation—and is deemed positive for gestational diabetes, the question then becomes, “How do we handle this?” The list of information imparted from care provider to patient should look something like this:
1.  Dietary modification
2.  Exercise program
3.  Insulin therapy and/or an oral hypoglycemic agent if the above two measures fail to bring blood glucose levels under control.

Now, there’s a big difference between telling a woman,

 

“You need to watch your sugar intake, you need to get some regular exercise, and we might have to put you on medication to lower your blood sugar if those first two things don’t work.  If we don’t get this under control, you’re likely to have a big baby that can’t be delivered vaginally…”

 

…and…

 

“…I’m going to refer you to a registered dietician for dietary counseling so you can learn how to reduce your overall dietary sugar intake and make the best food choices possible, as well as to a physical therapist who can design an appropriate exercise program for you.  If we can decrease your blood sugar levels—preferably without medication—we can decrease other complications associated with gestational diabetes, like too much insulin in his bloodstream and excess growth problems with your baby.”

 

The latter approach to these talking points could be a good segue into describing how fetuses that are exposed to chronically high levels of blood glucose become newborns with high insulin levels.  Following birth, when baby’s blood sugar levels equalize (faster than insulin levels) the newborn can experience a dangerously rapid hypoglycemia.  This explanation becomes a fact (not judgment)-based reason for motivating the woman to make whatever changes she can during the remainder of her pregnancy.  Because, of course, overweight women care about the well-being of their babies just as much as normal-weight women do.

Additionally, getting a jump-start on treating a pregnant woman’s high blood glucose levels through diet and exercise changes, can also influence her own long term well-being.  Because upwards of 50% of women who experienced gestational diabetes will go on to develop Type II Diabetes later in life (without treatment interventions) guiding a woman toward improving her dietary intake and activity levels sooner, will support a healthier existence, later. (Chu, et al)

However, by taking the short cut and simply telling a woman to ‘eat better and exercise more,’ a lot is being taken for granted:  we are assuming the woman knows about complex carbohydrates and simple carbs and their individual impact on blood glucose levels.  We are assuming she’s aware of the different glycemic loads of different foods.  We are assuming she knows how much constitutes a single serving, what her daily caloric intake is (or should be) and what changes in her diet would be optimal—along with which ones would be risky—for improving her outcome.  In using the former approach, we are also risking making our patient feel bad about her gestational diabetes status.  When people are made to feel ashamed of themselves, they tend to shut down and proverbially stick their fingers in their ears and cry, “Nah-nah-na-nah-nah…I can’t hear you!”  Conversely, giving our patients the tools to make themselves healthier prompts a sense of partnership between consumer and care giver that, ultimately, keeps the lines of communication open.

(More to come on influencing diet and exercise measures–including sociocultural issues– in a later post by Kristen Montgomery.)


Fetal Macrosomia
Both GD and maternal overweight/obesity are predictors of fetal macrosomia as described in this review article, published in the British Journal of Obstetrics and Gynecology (Volume 113, Issue 10, pages 1126–1133).  Unfortunately, suspected fetal macrosomia has been the impetus for elective induction—and sometimes elective cesarean delivery—when recent evidence does not support these practices.

In a cohort analysis of 11,681 deliveries (n=8,379 after inclusion criteria employed) by D.A Beyer, et al, the impact of maternal obesity on labor and delivery was assessed.  The study groups were broken into Control Group (BMI of 18 – 24.9) and Test Group (BMI > 25).  Results described a prolongation of labor of 1.6 hours between the normal weight and obese study participants, and newborn weight differences as follows:

Table 2. Maternal BMI and associated newborn weight

Group (mothers) Weight (newborn)
Control (BMI 18 – 24.9) 3,413g (7.52lb)
Overweight (BMI 25-29.9) 3,535g (7.79lb)
Obese (BMI 30-34.9) 3,508g (7.73lb)
Morbidly Obese (BMI >40) 3,682g (8.11lb)

This study deemed the differences in birth weights listed above as “significant,” as well as other  outcomes, such as shoulder dystocia (n=4—or 0.1%–in the control group, and n=6—or 0.2%–in test group) and primary cesarean delivery (n=975—or 21%–in the control group, and n=1055—or 26%–in the test group).  And yet, I’m not sure that these numbers are significant enough to justify for all obese pregnant women an automatic labor induction or primary c-section due to a 0.1 % increased risk of shoulder dystocia, or a 5% increased likelihood that a secondary cesarean should come to pass.

This cohort study by CSE Homer, et al, out of the UK (n=591) looking at outcomes for planned vaginal versus planned cesarean delivery in extremely obese women (BMI > 50) came to a similar conclusion:
“This study does not provide any evidence to support a policy of routine cesarean delivery for extremely obese women on the basis of concern of higher rates of delivery complications, but does support a policy of individualized decision making on mode of delivery based on a thorough assessment of potential risk factors for poor delivery outcomes.” [my emphasis]  (Under the “Results” section, the study authors describe previous c-section and pre-existing or gestational diabetes as increased risk factors for resultant c-section in the study group.)

Homer et al made an interesting point about should dystocia, in that dystocia is an inexact diagnosis. Some declare a dystocia if they have had to employ a particular maneuver to free the anterior shoulder from the mother’s pubic arch, while others define it as any delay between the delivery of the fetal head and the rest of his body.  This study reported a 2.2% incidence of dystocia in their study population (13/591), compared to general North American and UK rates of ~ 0.6%  and of the study participants in which a should dystocia was diagnosed, none led to lasting morbidities for mother or baby. 30% of the women who had planned a vaginal birth in this cohort went on to deliver by cesarean (slightly higher than the national rate of 24%).  When utilizing a study like this to determine practice guidelines, a clinician has a choice to make:  recommend primary cesarean deliveries for all obese or morbidly obese women because there is some risk of dystocia due to fetal macrosomy, or err on the side of supporting the pursuit of a vaginal delivery unless some other medical indication prompts an alternative decision (the presence of toxemia, for example).

The Cochrane Collabortation weighs in on the issue of elective labor induction to get a baby who is expected to be growing too large for gestational age through and out:  “Induction of labor for suspected fetal macrosomia is not supported with enough data to provide reliable evidence.” (Cochrane Pocketbook, Cochrane Collaboration and John Wiley & Sons, LTD. pg 222)

Statistically, the vast majority of overweight and obese women can deliver their babies vaginally. Barring particular medical complications suggesting otherwise, these mothers should be allowed to pursue a spontaneous delivery if that is their wish.

Many studies anecdotally report high cesarean delivery and induction rates in overweight or obese women yet do not relate the reasons for these outcomes.  Is it possible that provider fear or bias comes into play when an obese woman’s labor and delivery draws near?  Does the slightly longer labor length associated with obese women prompt clinicians to diagnose ‘failure to progress’ sooner than is warranted?  From the Baltimore Sun article referenced in our first post: “People don’t realize the risk we’re taking, by taking care of these patients,” said Dr. Albert Triana, [whose two provider practice does care for women of all sizes].  “There’s more risk of something going wrong and more risk of getting sued.”

Infection During and After Pregnancy for the Overweight or Obese Woman
This May 1st story on ScienceDaily.com brought to light new research out of Tufts University, postulating on the reason pregnant women of size have a harder time fighting off infection.

“Results showed that obese women had fewer CD8+ (cytotoxic T) cells and natural killer cells, which help fight infection, compared to lean women. In addition, obese pregnant women’s ability to produce [other] cells to fight infection was impaired.”  Additionally, recent research out of Guadalajara, Mexico informs us of the impact oxidative stress has on pregnancy:  namely, in the form of preeclampsia, when the oxidative stress reaches peak levels.  When this process progresses, maternal neutrophil levels spike—taxing the woman’s immune system.  Intuitively then, it makes sense that if pregnancy is a high oxidative stress state, (even more so, if pre-eclampsia develops) and obese women have a harder time fighting infection, putting this particular type of patient at an even higher risk for infection (namely via cesarean delivery) should be avoided whenever possible.  At the same time, women for whom cesarean delivery becomes a necessity, should be treated for infection prophylaxis according to their size, rather than standardized adult dosages, suggests new research like this by L. Pevzner et al out of the UC Irvine department of Obstetrics and Gynecology.

In its chilling maternal mortality report (CA-PAMR), the California Department of Public Health spends considerable time discussing the link between obesity and increased risk of both maternal morbidity and mortality.  But the report’s findings are not as simple as stating, ‘all obese women are at an increased risk of dying during our shortly after pregnancy.’  We must remember that not all women of size—whether in California, Colorado or elsewhere in the world—will develop pre-eclampsia, gestational diabetes, cardiomyopathy or other dangerous and potentially life-threatening illnesses.  And yes, larger than “average” women maintain the same types of desires as their leaner counterparts:  to bring forth a healthy baby into the world under the best possible circumstances.  To gain a better understanding of when obesity challenges that potential outcome, we must look at individual circumstances, like those reviewed above, as well as other non-medical factors.

[In tomorrow's post, we will take a closer look at the CA-PAMR, as well as difficulties caring for obese or extremely obese pregnant women from a care provider's perspective, and the role preventative medicine and education can take in improving care for this segment of our maternity population.]


Posted by:  Kimmelin Hull, PA, LCCE

Maternal Obesity , , , , , , , , , ,