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Cesarean Sections in the U.S.: The Trouble with Assembling Evidence from Data

The views expressed are those of the author and are not necessarily those of Scientific American.


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U.S. Cesarean Section Rates

Surgery detail

Surgery detail

Pregnancy, labor, and delivery have become increasingly medicalized in recent decades, leading to criticism from multiple factions. For instance, the rate of cesarean section in the U.S. (and in many other developed nations) draws fire from the World Health Organization (WHO), which suggests that the c-section rate should not rise above 15% [1].

There’s no doubt that the rate of c-section is high in the United States compared to elsewhere in the world. In 2009, cesareans accounted for 32.9% of all deliveries, up from 20.7% in 1996 [2]. Worldwide, rates of c-section vary tremendously, with cesarean rate being very nearly a proxy measurement for access to skilled birthing assistance. According to WHO, the least developed countries have c-section rates averaging around 2%, while the most developed regions average just above 20% [3]. In fairness, these numbers can’t be compared directly to the current c-section rate in the U.S., as they are several years old. At the time of the WHO report, the U.S. c-section rate was around 27.6%.

Induction of labor is a relatively common birthing intervention in the U.S., occurring in 23% of all pregnancies [2]. There is a well-established relationship between induction of labor and increased risk of c-section [4, 5], with one study estimating that induction itself contributed to eventual cesarean in approximately 20% of induced labors (other contributing factors aside) [6]. Another study suggested that induction more than doubled the likelihood of a c-section [7].

Is The Cesarean Rate A Problem?

While it’s tempting to look at the data and make the assumption that over-medicalization is responsible for the high rate of induction and c-section in the U.S. — and to further extrapolate that the high rate of c-section is responsible for increased maternal mortality — there are several problems with this interpretation. First, it goes without saying that c-sections, while not medically necessary in the majority of deliveries, are lifesaving for both mother and infant when medically required. Per WHO data, those undeveloped nations with the very lowest c-section rates have staggeringly high maternal mortality, with more than 1 in 100 labors resulting in the mother’s death. By comparison, maternal mortality in much of Europe and North America is in the range of 0.001 – 0.03% [3]. This somewhat deromanticizes the image of a native tribeswoman squatting in her hut, giving birth “as nature intended.” It’s easy to forget that if we desire completely natural childbirth, we have to accept the natural maternal and neonatal mortality that accompanies it.

Further, despite the link between induction and increased risk of c-section, judiciously used induction can actually prevent surgical intervention. A study of women at 41 weeks’ gestation found that those who underwent induction were 12% less likely to require a c-section than those allowed to go into labor naturally [8]. There’s also significant evidence that pregnancies that go past 42 weeks are associated with increased neonatal morbidity (harm) and mortality [9]. Given the relatively low percentage of American women — 5.5% — who give birth at or after the 42-week mark, however, appropriate use of induction in the case of a post-term fetus can’t explain the c-section rate in the U.S.

Judicious and appropriate use of the c-section aside, there’s considerable evidence that non-medically indicated c-sections pose a risk to the mother. A study that excluded women with complications of pregnancy found that c-section was associated with a threefold higher maternal mortality as compared to vaginal delivery [10]. Planned c-sections are quite a bit safer than unplanned c-sections, according to the data. One study showed no difference in maternal mortality or serious maternal morbidity between planned c-section and vaginal delivery [11], while another showed a reduced risk of certain negative maternal outcomes — including hemorrhage — with planned c-section [12]. A third showed a modest increase in risk to the mother with regard to normal complications of surgery (including wound bleeding, longer hospital stay, and reactions to anesthetic). There was no increase in maternal mortality as compared to vaginal delivery, however [13]. With regard to the infant, mortality and serious morbidity are significantly lower in the case of a planned c-section than in that of a planned vaginal delivery [11]. Neonatal morbidity and mortality risk in cases of unplanned c-section are difficult to quantify accurately, since complications resulting in the need for a c-section are significant confounding factors.

With regard to long-term effects of cesarean delivery on the infant, there’s been some interest in a so-called “hygiene hypothesis,” which suggests that vaginal delivery helps to colonize the infant gut with healthy bacteria [14]. As yet, however, this hypothesis is unproven. Studies have found no difference in long-term risk of death or developmental consequences associated with c-section delivery [15], and evidence supports the ability of the mother and infant to bond appropriately regardless of delivery type [16]. There is evidence that neonatal morbidity and mortality in a subsequent pregnancy are higher if the mother delivered by c-section in her first pregnancy [17]. However, this data is difficult to interpret in a meaningful way, since many c-sections are the result of complications of pregnancy, increasing the likelihood of a subsequent complicated pregnancy.

Based upon the data, it’s reasonable to conclude that an uncomplicated vaginal delivery is safest for mother and baby, while a planned c-section is safer than a complicated vaginal delivery that results in an unplanned c-section. Unfortunately, it’s impossible to know in advance who will have an uncomplicated vaginal delivery.

Possible Influences On Cesarean Section Rates

One theory regarding the high rate of c-sections in the U.S. as compared to those in certain other developed nations holds that the litigious nature of American society creates fear, and therefore overreaction, in the obstetrician. There’s some support for this theory; the likelihood of a c-section is indeed higher in cases in which there is greater risk of a malpractice suit [18]. Further, a survey of obstetricians revealed that physicians were more likely to comply with a request for cesarean delivery (in a medically ambiguous case) if they perceived a greater threat of litigation [19].

However, while the threat of suit may partially explain the c-section rate in the U.S. (in an unquantifiable way about which we may only speculate), it’s reasonable to assume that most obstetricians are interested first and foremost in good patient outcomes. After all, obstetrics is one of the medical specialties with the highest rates of lawsuit. If a physician’s sole motivation were to minimize the risk of litigation, that physician would be better off in another specialty.

There are other factors unique to the U.S., however, that could help explain the c-section rate. First, while obesity is a problem in much of the world, nowhere is it as epidemic as in the U.S. Currently, 36% of U.S. men and women are obese [20], while another third of Americans fall into the less severe “overweight” category [21]. No other nation comes close to competing; obesity rates are around 26% for both men and women in the U.K., and around 25% for both genders in Australia and New Zealand. In Italy and Germany, approximately 20% of the population is obese, with lower rates still in France. Sweden has 11% obesity among women, with a rate of 15% among men [20]. Excess body fat is associated with a significantly increased risk of complications of pregnancy, including gestational diabetes and high blood pressure [22]. Even among women who are not significantly overweight or obese pre-pregnancy, the rate of excess pregnancy-related weight gain is high, with 20.8% of pregnant American women gaining more than 40 pounds [2]. For comparison purposes, most women are advised to gain 25-35 pounds during pregnancy. Excess weight gain during pregnancy is, like pre-pregnancy overweight and obesity, associated with increased risk of gestational diabetes and other complications. The rate of gestational diabetes in the U.S. is currently 4.8%, while the rate of pregnancy-related high blood pressure is around 4%, an increase of 50% over 1990 levels [2]. Both obesity and diabetes significantly increase the risk of cesarean delivery [23, 24]. Excess body fat decreases the rate of cervical dilation and protracts labor, both of which increase the likelihood of cesarean. Overweight women are about 1.2 times more likely than normal weight women to require a c-section [25, 26], while obese women are around 1.7 times more likely than normal weight women to require a cesarean [26, 27]. Adjusted for American overweight and obesity rates, the 32.9% c-section rate becomes 26.15%, which is closer to the rates observed in leaner developed nations.

Obesity is not the only factor that fundamentally affects the c-section rate. One of the benefits of modern obstetric technology is that women can maintain higher-risk pregnancies than ever before. Further, women who are infertile or past their peak of fertility can receive reproductive assistance and become pregnant. Delivery by cesarean is strongly and positively associated with advanced maternal age; while the c-section rate in 2009 was 32.9% for all women, it was lowest in the youngest mothers (22.3% and 27.4% for women younger than 20 and 20-24 respectively), and highest in the oldest mothers (40.6% and 46.7% for women 35-39 and older than 40 respectively) [2]. From an evolutionary perspective, it’s intuitive that the women best able to deliver their babies vaginally would be the younger ones. For the majority of human history, the average life expectancy has been about 30 years [28], indicating that women did not evolve to engage in routine vaginal delivery into their 30s and 40s. That c-section rate is a proxy measure for availability of medical care isn’t necessarily an indication that practitioners, by definition, overuse c-section. The association must be at least partially attributed to the fact that the most developed nations — those with greatest access to medical care and some of the highest c-section rates — are those very nations in which women can utilize medical technology to conceive where they would otherwise be incapable of doing so.

Furthermore, women of advanced maternal age and those who receive fertility treatments of certain types have increased probability of giving birth to twins or higher order multiples. In fact, the rate of twins born in the U.S. has increased dramatically in recent years, nearly doubling since the 1980s. Increases have been highest among older mothers. In 2009 alone, the twin birthrate increased by 2% over that of 2008, while the rate of higher-order multiples rose by 4% in a single year [2]. These increases are typical of recent years. Interestingly enough, the c-section rate has also been climbing by about 2% a year. While this is an intriguing correlation, it’s not a basis for suggesting that the increased prevalence of multiples is solely responsible for the rising c-section rate. Still, as most twins and higher-order multiples are delivered by cesarean, there is certainly a connection.

Then, too, there’s the simple fact that the modern c-section has been performed for almost 150 years, which is enough time to observe changes in the prevalence of certain genes on a population level. Women with small or unusually shaped pelvic openings who produced babies too large to fit through the pelvis (fetal-pelvic disproportion) were once at a great reproductive disadvantage. Before the modern c-section, such a woman would have been unlikely to produce a living child (or unlikely to survive her first delivery, which would have limited her to a single child). This would have decreased the prevalence in the population of genes associated with the many factors that can lead to fetal-pelvic disproportion. Now, however, such women are no longer at a reproductive disadvantage in those populations in which the c-section is commonly practiced. As such, the associated genes could reasonably be expected to become more prevalent in those populations, thus necessitating increasing numbers of c-sections. This is yet another intriguing (albeit unproven) forcing that could affect c-section rate.

Making Sense Of The Information

The question at the heart of all this is Do obstetricians in the U.S. do too many unnecessary c-sections? Unfortunately, this question is very problematic to answer. The major impediment to drawing strong, scientific conclusions about this issue is that the majority of birthing studies are non-randomized. This leads to significant confounding of the data, and makes generalizations difficult. For instance, an obese woman (higher risk of c-section) is more likely to be inactive than a non-obese women (higher risk of c-section [29]), and is more likely to have high blood pressure and/or diabetes than a non-obese women (higher risk of c-section). She’s also at higher risk of carrying a fetus with congenital abnormalities (30), which could negatively impact fetal health and increase the risk of a c-section. An obstetrician, knowing that this woman is at higher risk of a c-section, could very naturally approach the situation expecting to end up doing a c-section (and worrying about his liability because of this high-risk patient), both of which increase the patient’s risk of having a c-section. If, in the end, the woman has a c-section, is it because she needed it, or because she had so many risk factors that it didn’t make sense to wait? After all, the odds of a good outcome in a planned c-section are better than the odds of a good outcome in an emergency c-section, and the former is only slightly riskier to the mother — and is less risky to the baby — than a planned, uncomplicated vaginal delivery. Further, calculating the risks (to either mother or baby) associated with an emergency c-section is a difficult thing; after all, a c-section wouldn’t have been done on an emergent basis if there weren’t some indication of either maternal or fetal distress. It is therefore problematic to separate morbidity and mortality associated with the root cause of the distress from morbidity and mortality attributable to the surgery.

Ultimately, the c-section rate in the U.S. is likely affected by a number of factors, but may also owe much to risk-to-benefit analysis conducted by well-intentioned obstetricians, who are interested in maximizing maternal and neonatal wellbeing. Given that there are situations in which uncomplicated vaginal delivery is less likely, and given that a planned c-section is much safer than an emergency c-section, an obstetrician with any inkling that a patient could end up needing surgical intervention might reasonably conclude that scheduled surgery is the least risky of the available routes. It’s very easy — assuming the baby was delivered successfully and the mother is well — to look back on a c-section and call it unnecessary. This assertion, however, can’t be proven; it’s possible that both mother and baby would have come through a vaginal delivery in good health, but it’s also possible that the c-section was lifesaving. After the fact, there’s no way to know. In the end, the only cesarean that we can be absolutely certain was necessary is the one that, tragically, wasn’t done in time.

References:

1) World Health Organization. Appropriate technology for birth. Lancet. 1985 Aug 24;2(8452):436-7.

2) Martin et al. Births: final data for 2009. Natl Vital Stat Rep. 2011 Nov 3;60(1):1, 1-72.

3) Betran et al. Rates of caesarean section: analysis of global, regional and national estimates. Paediatr Perinat Epidemiol. 2007 Mar;21(2):98-113.

4) Burgos et al. Induction at 41 weeks increases the risk of caesarean section in a hospital with a low rate of caesarean sections. J Matern Fetal Neonatal Med. 2012 Feb 17. [Epub ahead of print]

5) Wilson et al. The Relationship Between Cesarean Section and Labor Induction. J Nurs Scholarsh. 2010 Jun;42(2):130-8.

6) Ehrenthal et al. Labor induction and the risk of a cesarean delivery among nulliparous women at term. Obstet Gynecol. 2010 Jul;116(1):35-42.

7) Seyb et al. Risk of Cesarean Delivery With Elective Induction of Labor at Term in Nulliparous Women. Obstet Gynecol. 1999 Oct;94(4):600-7.

8) Sanchez-Ramos et al. Labor Induction Versus Expectant Management for Postterm Pregnancies: A Systematic Review With Meta-analysis. Obstet Gynecol. 2003 Jun;101(6):1312-8.

9) Rand et al. Post-Term Induction of Labor Revisited. Obstet Gynecol. 2000 Nov;96(5 Pt 1):779-83.

10) Kamilya et al. Maternal mortality and cesarean delivery: An analytical observational study. J Obstet Gynaecol Res. 2010 Apr;36(2):248-53.

11) Hannah et al. Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Lancet. 2000 Oct 21;356(9239):1375-83.

12) Geller et al. Maternal Outcomes Associated with Planned Vaginal Versus Planned Primary Cesarean Delivery. Am J Perinatol. 2010 Oct;27(9):675-83. Epub 2010 Mar 16.

13) Liu et al. Maternal mortality and severe morbidity associated with low-risk planned cesarean delivery versus planned vaginal delivery at term. CMAJ. 2007 Feb 13;176(4):455-60.

14) Neu et al. Cesarean versus vaginal delivery: long-term infant outcomes and the hygiene hypothesis. Clin Perinatol. 2011 Jun;38(2):321-31.

15) Whyte et al. Outcomes of children at 2 years after planned cesarean birth versus planned vaginal birth for breech presentation at term: The international randomized Term Breech Trial. Am J Obstet Gynecol. 2004 Sep;191(3):864-71.

16) Durik et al. Sequelae of cesarean and vaginal deliveries: Psychosocial outcomes for mothers and infants. Dev Psychol. 2000 Mar;36(2):251-60.

17) Huang et al. Cesarean delivery for first pregnancy and neonatal morbidity and mortality in second pregnancy. Eur J Obstet Gynecol Reprod Biol. 2011 Oct;158(2):204-8.

18) Localio et al. Relationship Between Malpractice Claims and Cesarean Delivery. JAMA. 1993 Jan 20;269(3):366-73.

19) Fuglenes et al. Obstetricians’ choice of cesarean delivery in ambiguous cases: is it influenced by risk attitude or fear of complaints and litigation? Am J Obstet Gynecol. 2009 Jan;200(1):48.e1-8. Epub 2008 Oct 30.

20) International Obesity Taskforce

21) U.S. Centers for Disease Control and Prevention

22) Sebire et al. Maternal obesity and pregnancy outcome : a study of 287213 pregnancies in London. Int J Obes Relat Metab Disord. 2001 Aug;25(8):1175-82.

22) Ehrenberg et al. The influence of obesity and diabetes on the risk of cesarean delivery. Am J Obstet Gynecol. 2004 Sep;191(3):969-74.

23) Dempsey et al. Maternal pre-pregnancy overweight status and obesity as risk factors for cesarean delivery. J Matern Fetal Neonatal Med. 2005 Mar;17(3):179-85.

24) Nuthalapaty et al. The Association of Maternal Weight With Cesarean Risk, Labor Duration, and Cervical Dilation Rate During Labor Induction. Obstet Gynecol. 2004 Mar;103(3):452-6.

25) Vahratian et al. Maternal Pre-pregnancy Overweight and Obesity and the Risk of Cesarean Delivery in Nulliparous Women. Ann Epidemiol. 2005 Aug;15(7):467-74.

26) Raatikainen et al. Transition from Overweight to Obesity Worsens Pregnancy Outcome in a BMI-dependent Manner. Obesity (Silver Spring). 2006 Jan;14(1):165-71.

27) Weiss et al. Obesity, obstetric complications and cesarean delivery rate–a population-based screening study. Am J Obstet Gynecol. 2004 Apr;190(4):1091-7.

28) Hayflick, L. The future of ageing. Nature. 2000 Nov 9;408(6809):267-9.

29) Melzer et al. Effects of recommended levels of physical activity on pregnancy outcomes. Am J Obstet Gynecol. 2010 Mar;202(3):266.e1-6. Epub 2009 Dec 22.

30) Leddy et al. The Impact of Maternal Obesity on Maternal and Fetal Health. Rev Obstet Gynecol. 2008 Fall;1(4):170-8.

Kirstin Hendrickson About the Author: Kirstin Hendrickson is a science journalist and faculty in the Department of Chemistry and Biochemistry at Arizona State University. She has a PhD in Chemistry, and studied mechanisms of damage to DNA during her graduate career. Kirstin also holds degrees in Zoology and Psychology. Currently, both in her teaching and in her writing, she’s interested in methods of communicating about science, and in the reciprocal relationship between science and society. She has written a textbook called Chemistry In The World, which focuses on the ways in which chemistry affects everyday life, and the ways in which humans affect each other and the environment through chemistry. She blogs about evidence-based parenting and analyzes parenting-related research at SquintMom.com. Follow on Twitter @SquintMom.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 19 Comments

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  1. 1. jtdwyer 10:02 am 03/28/2012

    Overlooking for the moment that the fundamental problem with “The Trouble with Assembling Evidence from Data” is the improper interpretation and inadequate evaluation…

    “…despite the link between induction and increased risk of c-section, judiciously used induction can actually prevent surgical intervention.”

    Without access to any formal data, I understand that the number of deliveries in hospitals ebb and flow throughout the day in harmonic frequencies with hospital staff shift schedules, and that U.S. hospitals prefer to induce labor in order to maximize the efficiency of their staff. As I understand, you also suggest that there is a causal relationship between induction and requirements for cesarean deliveries. Doesn’t this suggest that it is the operational policies of hospitals that principally determines the number of cesarean deliveries in the U.S.?

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  2. 2. killgrove 10:10 am 03/28/2012

    Thanks for this excellent article. It’s refreshing to see such a comprehensive analysis of all the factors that go into one bit of information: did C-section rates go up or down? As you point out, it’s not that simple. To suggest that it is that simple is to ignore the amazing variability and complexity of the human body (and the culture that helps produce it, of course). This will be a great piece to assign students the next time I teach biological anthropology.

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  3. 3. r0b3m4n 1:39 pm 03/28/2012

    Always the economist, one small (hopefully VERY small) cause of higher C-section rates is money. A planned C-section has a higher rate of Maternal survival, hence doctors/hospitals should financially be more interested in maximixing maternal survival since it makes it more likely the medical bill will be paid.

    Along other economic lines, c-sections probably are more money income (for medical supplies companies, doctors, hospitals, reduced litigation) so I’m sure there is a small conflict of interest in the money making categories also. Yes I’m sure that almost all Dr’s care more about patient health than a few bucks. But, in these economic times I wouldn’t rule this factor out entirely (that ferrari CAN’T be cheap…)

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  4. 4. Jill Arnold 2:49 pm 03/28/2012

    “However, while the threat of suit may partially explain the c-section rate in the U.S. (in an unquantifiable way about which we may only speculate)”

    This has been somewhat quantified (but not really).

    Doctors are the first to admit that the c-section rate is driven by fear of lawsuits, such as in this quote from ACOG’s immediate past president: “Unfortunately we don’t get sued for doing C-sections. We get sued for not doing C-sections soon enough,” said Dr. Waldman. “That has really increased, I think, our C-section rate.”

    (http://www.9wsyr.com/content/family_healthcast/story/Health-Alert-C-section-births-VBACs/CKnu5DP6tUCz0gNjutk-UA.cspx)

    So if we know that fear of lawsuits and defensive medicine is driving up cesarean rates, then we can look at how a recent ACOG survey of its members quantified the use of defensive medicine. According to a 2009 survey, “63% have made one or more changes to their practice as a result of the risk or fear of professional liability claims or litigation.”

    (http://www.acog.org/About_ACOG/News_Room/News_Releases/2009/ACOG_Releases_2009_Medical_Liability_Survey)

    “It’s very easy — assuming the baby was delivered successfully and the mother is well — to look back on a c-section and call it unnecessary. This assertion, however, can’t be proven”

    This is true in the sense that what *could* have happened can never truly be retrospectively proven (in life in general, not just birth). However, it is pretty easy to look at populations, rather than individual patients, to analyze procedure utilization. With larger numbers, you can control for things like patient characteristics and reveal what is referred to as unwarranted practice variation between physicians and hospitals. It distills everything down to more subjective issues, like physician and/or patient preference, culture, risk tolerance, etc., which can in part answer whether a section was not indicated medically but desired, in which case it might have been medically unnecessary but not unnecessary to the patient in terms of preference.

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  5. 5. apbsc 7:59 pm 03/28/2012

    Is it possible to get the c-section rate of a specific doctor and/or hospital?

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  6. 6. SquintMom 9:40 pm 03/28/2012

    @apbsc — you should be able to do so, yes. You’d ask the doctor. As for the hospital, I’m not sure. Try calling labor/delivery, however, and they should be able to direct you to the right place.

    Remember, though, that just the c-section rate isn’t necessarily helpful. A doctor could have a high c-section rate because she does lots of non-medically indicated cesareans, or she could take a lot of high-risk patients. She could have a great reputation as an OB for people who’ve conceived via fertility treatment, or she could have a great reputation as an OB for moms of multiples…

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  7. 7. catsar 9:47 pm 03/28/2012

    Wow. The author states “With regard to the infant, mortality and serious morbidity are significantly lower in the case of a planned c-section than in that of a planned vaginal delivery [11].” This is pretty much the only outcomes data the author offered for c-section vs vaginal birth at term.

    Somehow the author has managed to totally ignore that source #11 is a study on breech presentation births. Its relevance to the majority of births is questionable at best. While it is certainly useful to know how breech births should be handled for best outcomes (although there are provider training issues that may be muddling the waters here), the relevance of a study on breech presentations to a more general vaginal vs cesarean birth decision is a mighty big stretch. If the author has no better data on infant outcomes than this breech data, her conclusions on infant outcomes are mighty overstated.

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  8. 8. electivecesarean.com 4:07 pm 03/29/2012

    This article perhaps might have been subtitled, “The Trouble with Assembling Evidence from Mixed Cesarean Data”.
    One of the biggest problems in the ongoing cesarean debate is the number of research studies that rely on mixed cesarean data (i.e. they do not separate planned and emergency surgeries, or planned surgery ‘for a medical/obstetrical reason’ and planned surgery ‘on maternal request’ alone). Similarly, there are too many research studies that do not properly compare intent to treat (i.e. a comparison of each planned mode of delivery and ALL the actual outcomes of each).
    Going forward, we need better data collation, more standardized methods for comparison of different birth plans, and a willingness to include the longer term health and cost outcomes (e.g. incontinence and prolapse) of each birth plan.
    There is a great deal of truth in the last paragraph of this article, and while the U.S. does might not yet have achieved the correct balance in terms of wanted and unwanted cesareans, it’s worth remembering that in many other countries, the ideological focus on normalizing birth at all cost has resulted in tragic outcomes for some mothers who pleaded for a cesarean birth but were ignored.
    Pauline Hull, co-author
    Choosing Cesarean, A Natural Birth Plan

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  9. 9. la.mama.loca 6:29 pm 03/29/2012

    The WHO no longer says that no more than 15% of births should be cesareans. In fact, in the latest edition of Monitoring Emergency Obstetric Care, they admit that the 15% number had no empirical evidence in support of it, and that the ideal rate of cesareans is unknown.

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  10. 10. la.mama.loca 6:33 pm 03/29/2012

    This article has some good information on the outcomes for baby for planned cesarean versus planned vaginal delivery: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2475575/

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  11. 11. SquintMom 2:21 pm 03/31/2012

    Actually, @la.mama.loca, the notion that WHO rescinded this statement is false. There was a press release that incorrectly made this claim, and the misinformation has been propagated on the Internet. The truth of the matter is that the WHO handbook still states “It should be noted that the proposed upper limit of 15% is not a target to be achieved, but rather a threshold not to be exceeded.”

    Please see http://www.who.int/reproductivehealth/publications/monitoring/9789241547734/en/

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  12. 12. Jill Arnold 9:26 am 04/2/2012

    @apbsc No to provider-level rates except in Virginia (and yes to Squint Mom’s call for context).

    This is the most recent publicly available facility-level data available in the U.S. at this point in time: http://www.cesareanrates.com.

    Note the caveat about the data: http://www.cesareanrates.com/data/

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  13. 13. veritasliberat 1:37 pm 06/8/2012

    Re: comments 9 and 11: you’re both right. Right before the quote from the WHO handbook cited in #11 by Squintmom, it mentions that although the WHO has had the 15% upper limit for years, “there is no empirical evidence for an optimum percentage or range of percentages.”
    It sounds as though the WHO is saying, here’s our recommendation, we like the 15% number even though we have nothing to back it up with.

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  14. 14. MimiReed 9:10 am 09/26/2012

    This column is unfortunate and, in a few places, absurd.

    1). Life expectancy. Life expectancy at birth does not reflect life expectancy at adulthood. Even in the most violent and materially deprived societies, a woman who reaches the age of menarche can expect to reach the age of at least 35. Women have always been bearing children past 30.

    2). Maternal nutritional status. Women gain too much weight in pregnancy because for the last 20 years, ob/gyns have encouraged them to. It is only recently that recommendations of 25 to 35 lbs were pushed for normal weight mothers–and the weight of the evidence shows that this is far too high and that a better recommendation would be 15-25 lbs. Doctors are creating this problem that a c-section “solves.”

    3). Bad hip hypothesis. Sorry, but this is just stupid. In healthy adult women, a c-section is virtually never needed because a baby is “too big.” Skeletal deformity was once the leading reason for c-sections because of nutritional deficits and chronic diseases that are unheard of today. (This began the “too big” baby myth.) These conditions are not genetic, and there are not thousands of tiny-hipped women, evolutionary dead ends, running around, requiring c-sections.

    4). Fertility treatment hypothesis. The rate of multiple births in the United States has doubled due to fertility treatments. To 3.2%. A one and a half percent rise in multiple births does not account for a c-section rate double of what it should be. In addition, many of the most common reasons for infertility do not in any way raise the risk of complications–tubal problems, for one.

    5). Saving at-risk babies hypothesis. While we have made enormous strides at saving at-risk babies after birth, there is very, very little that can be done to save at-risk babies before birth. The only treatments are iv fluids, a careful diet, magnesium sulfate to delay birth a couple of days, and steroids to develop a baby’s lungs. That is it. Cervical stutures, progesterone supplementation, heparin imjections, bed rest–all of these are voodoo science. It makes sense that they should work….but the research does not support their use. If we are really saving tons of babies through these c-sections, then our infant mortality would reflect this. It does not.

    The only hypotheses that hold any weight at all are that older mothers are more likely to have c-sections and overweight mothers are, too, but these are both fraught with complicating factors. Older first time mothers are also more easily persuaded into medical interventions that are unnecessary, especially if they plan for this to be their only child. Overweight mothers are are not only in poorer health, but they are also instructed to gain dangerous amounts of weight. (The best studies show that obese mothers should gain 0 to 5lbs in pregnancy. They are being told to gain 15.). Even in these circumstances, it isn’t “just the moms.”

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  15. 15. MimiReed 9:17 am 09/26/2012

    The vastly different c-section rates between equally equipped hospitals is one damning piece of evidence against the claim that all these c-sections are needed.

    The most damning, however, is that the likelihood of your birthing experience turning into a c-section is best predicted by the length of time since you were admitted, regardless of dilation status at admission, and the nearness to the end of the current shift. Neither if these has anythingnto do with your wellbeing–but both are more convenient for the doctor and profitable for the hospital.

    Link to this
  16. 16. cassienova 7:40 pm 12/1/2012

    The cesarean section can be a fantastic tool if used properly. Many times a cesarean is scheduled or performed with no medically necessary reason. The risks of major abdominal surgery to both mother and child should not be taken lightly. Medical interventions are discovered to help mothers and babies who need them to survive, and should not become routine. The cesarean rate in the United States is too high, due to many different issues, convenience, insurance and trigger happy physicians to name a few. Cesareans should not become routine, but only used when necessary.

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  17. 17. acorn 6:38 am 02/26/2013

    There are serious flaws in the logic of this article and its use of cited research.
    For example, the ‘intriguing correlation’ posited between a 2% rise in twin birthrates and a 2% rise in c-section rates makes no sense, as the twin birthrate is a tiny fraction of birthrates as a whole, so what the two numbers indicate is a far greater rise in C section rates, completely disproportionate to the increase in twin births!
    The blog also states, ‘With regard to the infant, mortality and serious morbidity are significantly lower in the case of a planned c section than in that of a planned vaginal delivery’, but the referenced study was of breech deliveries, a very high risk situation for vaginal birth.
    As for obesity, while a resultant risk is well-supported, actual demographic statistics of the use of C-sections for obese women are needed here. (Obesity also correlates with poverty, but C-sections do not!)
    In sketching the big picture, the author fails to note that the developed countries with the lowest prenatal mortality rates have low, not high, C-section rates(cf. Scandinavia, the Netherlands).
    Please, let’s strive for clear thought wherever we can.

    Link to this
  18. 18. acorn 6:39 am 02/26/2013

    sorry, a typo correction from acorn: perinatal mortality rates, not prenatal!

    Link to this
  19. 19. epidemiologyfan 7:14 pm 09/2/2014

    It’s hard to take an article like this who takes literally evidence completely out of context.

    I am most perturbed about the following:
    “With regard to the infant, mortality and serious morbidity are significantly lower in the case of a planned c-section than in that of a planned vaginal delivery [11].”

    Firstly, the Term Breech Trial (what source #11 comes from) was strictly comparing planned C-section to spontaneous labor and subsequent vaginal birth. Many credible authors since have torn the Term Breech Trial’s results apart for serious methodological violations that simply discredit any conclusions put forth by these authors. This paper does a fantastic job in explaining these methodological violations in painstaking detail – Glezerman, M. (2006). Five years to the term breech trial: the rise and fall of a randomized controlled trial. American journal of obstetrics and gynecology, 194(1), 20-25.

    A number of large-scale systematic reviews have since clarified that VBACs are a safe possibility for most women with a prior cesarean section delivery, one of which can be found here – Guise, J. M., Eden, K., Emeis, C., Denman, M. A., & Marshall, N. (2010). Vaginal birth after cesarean: new insights.

    Also, while ACOG’s guidelines have yet to revise their restrictive guidelines originally from 1999 in requiring the immediate availability of a physician in a VBAC attempt, their recent update of their guidelines on C-sections by maternal request have prioritized physician focus on encouraging vaginal birth whenever possible.

    Even though C-sections are useful for certain medical presentations, they do increase the risk of maternal and neonatal morbidity compared to uncomplicated vaginal birth. Most pregnancies and subsequent births are low-risk, even with the increase of ART and the average age of a pregnant woman.

    Tort reform is needed to relax the fears of physicians of being sued for even the slightest mistake in the delivery room. Obstetricians are only second to neurosurgeons in malpractice claims, and various observational studies have linked increased malpractice premiums and increased liability to increased utilization of C-sections. This is a great recent paper explaining the historical progression of liability fears and obstetrician behavior – Schifrin, B. S., & Cohen, W. R. (2013). The effect of malpractice claims on the use of caesarean section. Best Practice & Research Clinical Obstetrics & Gynaecology, 27(2), 269-283.

    We need to stop focusing on the prevalence of Cesarean delivery, and encourage physicians to utilize C-section whenever it is most appropriate for the mother and neonate. Not because of provider or patient fear, or uncertainty, or adherence to a specific aggregate threshold.

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