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Consider the Source: An interview with third-stage care researchers, Kathleen Fahy and Carolyn Hastie

December 30th, 2009 by avatar

Last summer, I was speaking to a producer of one of the popular cable TV so-called “reality” shows about the births he had witnessed. He said his crew had filmed only one home birth, and the woman had a severe postpartum hemorrhage requiring ambulance transport to the hospital. (She recovered fully.)  It’s not that such transfers never happen – the research literature cites a rate around 0.6-1.2% of planned home births – but I wondered why it had to happen in that particular birth for the whole world to see.  It occurred to me that one possibility is that the presence of a camera crew may have in fact predisposed the woman to excess blood loss.

A theory put forth in a new paper by Carolyn Hastie and Kathleen Fahy suggests that there may be something to my hunch. In Optimising psychophysiology in third stage of labour: Theory applied to practice, the two Australian researchers discuss how environmental factors such as lack of privacy, bright lights, and the presence of strangers may disrupt the normal hormonal adaptations that occur in the immediate postpartum period. They apply a theory of “midwifery guardianship” to propose optimal care in the third stage of labor (that is, after the birth of the baby until the birth of the placenta). For this second installment of our Consider the Source series, Dr. Fahy agreed to answer some questions about Carolyn Hastie’s and her work. We talked about the what the research on active third stage management does and doesn’t tell us, why midwifery theory matters, and best practices in conducting research on the prevention of postpartum hemorrhage in low-risk women.

Thank you to both of these important researchers!

Science & Sensibility: In your article, “Optimising psychophysiology in third stage of labour: Theory applied to practice,” you critically review the evidence for active management of the third stage of labor. What are some of the strengths and limitations of that body of literature?

: My full critique of the four randomised trials and the Cochrane meta-analysis of Active versus Expectant 3rd Stage Management has been published. In Australia, NZ and the UK the policy to use ‘active management’ of the third stage is based on the aforementioned research. My critique argues that existing studies do not provide a valid reason for imposing active management on women who are at low risk of postpartum hemorrhage. Subject selection in the randomised trials was not restricted to woman who were at low risk of postpartum haemorrhage and therefore they cannot be satisfactorily generalized to women who are at low risk. The study samples included a substantial proportion of women who are at known risk of postpartum hemorrhage which biases the results of the randomised trials and the Cochrane Review which is based on them.  Secondly, none of the randomised trials were able to report on the provision of third stage of labour care where all the components of holistic psychophysiological third stage were included in the study, where care was given to women in a home or home-like environment, and where the midwives had the right knowledge, attitudes and skills to support normal physiological processes.  Indeed, my analysis shows that in the trials underpinning the Cochrane review ‘expectant management’ is best described as ‘not active management’ rather than an entirely different midwifery model of third stage care.   What we mean by holistic psychophysiological care is detailed in our paper “Optimising psychophysiology in third stage of labour”. In essence, a midwife supports a woman to safely experience an undisturbed third stage by ensuring all of the following: 1) the woman is well prepared to work with the natural process of placental birth; 2) the woman feels loved and that she is in safe environment 3) the woman and baby are healthy 4) labour and birth have been undisturbed; 5) the midwife knows how to act as a  guardian in undisturbed third stage and 6) both woman and midwife are willing to switch to active management if the situation changes. Research about the effectiveness of midwifery care in undisturbed third stage for women at low risk of PPH urgently needs to be conducted.

Kathleen Fahy

Kathleen Fahy

Fahy

Science & Sensibility: Many midwives practicing in birth centers or the home birth setting do not routinely use active management of third stage, despite the fact that active management is supported by “Level 1″ evidence, recommended by national and international bodies, and generally considered the standard of care within the obstetric community. Based on your analysis of the research, are women giving birth in these settings at excess risk of problems related to postpartum blood loss?

: There is no research evidence about third stage care for the group of women who are at low risk and electing to birth at home or in a birth centre with a skilled midwife.  We are clear that supporting a woman to birth her placenta in a psychophysiological manner is not ‘expectant management’ as defined in the Cochrane Review. Optimising psychophysiology in third stage of labour requires both the woman and midwife to be knowledgeable and the midwife really needs to be skilled and experienced in this form of 3rd stage care.

Carolyn Hastie

Carolyn Hastie

Fahy

Our research team have submitted a paper that reports on a cohort study which compared the PPH outcomes for women who were at low risk of PPH based on whether they were intending to have an active or physiological third stage of labour.  We compared the results for a major maternity unit and a midwifery-led stand alone birth centre.  The results are very pleasing but we cannot declare them publically until the paper is published. Sorry!

Science & Sensibility: You developed the theory of Birth Territory and Midwifery Guardianship and apply it to third stage care in your article. Why is it important to develop midwifery theory? What is involved with theory development? How can or should theory influence research and practice?

Fahy: Scientific knowing should be based on both theory and evidence. The evidence should confirm or change the theory and the theory should suggest the research questions and provide a logical framework for understanding and applying research evidence. In the drive for evidence-based practice we have almost lost the link between theory and evidence which is central to both science and to practice.

In a simple sense ‘theories’ are the stories we tell ourselves about what is, has or will happen: most of our theories are informal and untested.  In order to develop and test a theory for practice the first step is to write it down as a scientific theory.

A scientific theory presents a systematic view of phenomena by specifying the inter-relationships between concepts using definitions and propositions. The purpose of scientific theory is to describe, explain and predict (in our case about midwifery practice). A concept is an abstract idea of phenomena, objects or actions. For example, two concepts from Birth Territory Theory are ‘terrain’ and ‘jurisdiction’. The concept of ‘terrain’ denotes the physical features and geographical area of the individual birth space, including the furniture and accessories that the woman and her support people use for labour and birth. ‘Jurisdiction’ means having the power to do as one wants within the birth environment. ‘Power’ is an energy which enables one to be able to do or obtain what one wants.   Propositions are statements of relationship between two or more concepts. Propositional statements provide theory with descriptive, explanatory or predictive powers. For example, a propositional statement in the theory of Birth Territory is “the less familiar the environment is to the woman the more likely she is to feel fear and uncertainty”.

Science & Sensibility: Many people are familiar with conventional risk factors for postpartum hemorrhage, such as induction of labor, an overdistended or exhausted uterus, and maternal clotting abnormalities. In your paper you list other risk factors, including “lack of midwifery guardianship by a trusted midwife,” “lack of appropriate birth environment (e.g., bright lights, cold temperature, noisy, strangers in teh room), and “lack of immediate and sustained mother and baby skin-to-skin contact.” What is the basis for your assertion that these pose a significant risk of excess blood loss?

Fahy: Carolyn and I learn more about this all the time.  It seems that bioscience; particularly the fields of neuro-biology and psychophysiology, are now confirming what Carolyn’s 30 years+ of homebirth practice of working with women had taught her.  In a nutshell woman and babies need to feel safe, warm and loved in order for their psychobiology to function optimally. We have added a few references so that you can see the ever increasing field of study which explores the role of intentional and attentional brain processes, stress response and environmental factors which impact a woman and baby’s psychophysiology and lead to either disruption in or optimisation of normal physiological functioning.   We could give you a huge number of references from a number of scientific fields. Here is a good start.

Cacioppo, J. T., Tassinary, L. G., & Berntson, G. G. (2007). Handbook of psychophysiology (3rd Edition ed.). New York: Cambridge University Press.

Lipton, B. H. (2005). The Biology of Belief. Santa Rosa: Mountain of Love/Elite Books.

Rossi, E. L. (2002). The Psychobiology of Gene Expression (First ed.). London: WW Norton & Company.

Sandman, C. A., Glynn, L., Wadhwa, P. D., Chicz-DeMet, A., Porto, M., & Garite, T. J. (2003). Maternal Hypothalamic-Pituitary-Adrenal Disregulation during the Third Trimester Influences Human Fetal Response. Developments in Neuroscience, 25, 41-49.

Segerstrom, S.C. & Miller, G.E. (2004) Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry, Psychology Bulletin, 2004 July; 130(4): 601-630. doi: 10.1037/0033-2909.130.4.601. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1361287

Sterling, P. (2004). Principles of Allostasis: optimal design, predictive regulation, pathophysiology and rational therapeutics. In J. Schulkin (Ed.), Allostasis, Homeostasis, and the costs of Adaptation (pp. 36). Cambridge: Cambridge University Press.

Tops, M., van Peer, J. M., Korf, J., Wijers, A. A., & Tucker, D. M. (2007). Anxiety, cortisol, and attachment predict plasma oxytocin. Psychophysiology, 44(3 %R doi:10.1111/j.1469-8986.2007.00510.x), 444-449.

Tsigos, C., & Chrousos, G. P. (2002). Hypothalamic-pituitary-adrenal axis, neuroendocrine factors and stress. Journal of Psychosomatic Research, 53(4), 865-861.

Uvnas-Moberg, K. (2003). The Oxytocin Factor: Tapping the hormone of calm, love and healing. Cambridge: Da Capo.

Wadhwa, P. D., Culhane, J. f., Rauh, V., Barve, S. S., Hogan, V., Sandman, C. A., et al. (2001). Stress, infection and preterm birth: a biobehavioural perspective. Paediatric and Perinatal Epidemiology, 15 (Supplement), 17-29.

Science & Sensibility: In your article, you describe in great detail the elements of physiologic care in the third stage of labor. As someone who spends a lot of time reading the scientific literature, I know that descriptions of the process and context of intrapartum care are extremely limited or absent in many studies, which makes it impossible to know what factors were at work in the background that may have contributed to observed outcomes.  In your opinion, what are the most important factors of the birth environment or care process that researchers should describe when they publish their findings on third stage outcomes? Can these be objectively measured and described?

Fahy: Wow, that is a hard question.  I often compare the flimsy way that obstetric interventions are described and not quality controlled at all with the detailed definitions and careful quality controls that are included for a drug trial (e.g. chemical makeup, dosage, storage, route of administration, interactions to be avoided, etc).  This is a major problem with the RCTs for 3rd stage care and also for the Breech Trial. (That was a disaster of junior doctors who didn’t know how to assist women to birth certain presentations of breech babies vaginally being given the responsibility of supervising the births; no wonder that in Western countries the results were poor but in developing countries where the skills for breech births have not been lost the outcomes were better for vaginal birth group).

So, I think a careful protocol needs to be developed in all the detail that is necessary. Only staff who have been taught and tested in providing the intervention should be allowed to provide it.  There should be ongoing QA during the trial.  A summary of the protocol, training and QA should be included in the published research report but the full protocol should be available upon request for critique and replication purposes.

Science & Sensibility: What research are you currently working on or planning?

Fahy: I am currently involved in a) a qualitative study of women’s experiences of attending the emergency department with bleeding or pain in early pregnancy. b) a retrospective cohort study to determine the relative strength of the presumed ’causes’ of PPH. c) I’m chief investigator of the following studies being done by PhD students: ‘Group-based antenatal education for Thai women who are at risk of preterm birth’;  ‘A theory and evidence-based intervention to promote and prolong breastfeeding’; ‘Factors affecting midwives’ decision-making in 2nd stage labour’; ‘What can a midwifery manager do to reduce PPH rates at a tertiary maternity unit; ‘Group-based antenatal education aimed at reducing perineal trauma for women in Malaysia: what do women want?’  My wonderful graduating PhD student Jenny Parratt is about to submit her PhD on “How do women change in the childbearing year and what factors have a positive impact on their sense of self?”

Carolyn’s Masters Research concerned inter-professional interactions between doctors and midwives in delivery suite and the perceived impact of these interactions on the health outcomes for women and babies. Her PhD is concerned with developing, with women, an internet-based antenatal education program. Carolyn is also co-supervising 3 of my PhD students (above).

Kathleen Fahy is an Australian professor of midwifery, a researcher, a theorist, a writer and a practitioner. She is the mother of two daughters and is in a happy partnered relationship, with a lovely network of supportive friends and family. When not thinking about how to make pregnancy, birth and early mothering a healthy and happy experience Kathleen likes to walk in nature and practice Tai Chi.

Carolyn Hastie is a mother, grandmother, midwife and academic who has worked in private practice midwifery and education for over 35 years. Carolyn recently established a public health, stand alone midwifery-led maternity service including homebirth services in NSW, Australia which was awarded, following three years operation,  Best Health Care Unit of the Hunter New England Area Health Service. Carolyn is now at the University of Newcastle teaching midwifery.

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Childbirth Literacy: What We’re Up Against

December 21st, 2009 by avatar

If anyone is wondering whether good quality childbirth education is necessary in our “information age”, the past month offers three compelling reasons to think that women remain profoundly in need of a trustworthy, reliable resource for learning how to have safe and healthy birth experiences.

1. The December issue of Obstetrics & Gynecology reports results of a survey by UnitedHealthcare of 650 insured women who had given birth to their first child within the previous 18 months. Researchers asked the mothers, “At what gestational age do you believe the baby is considered full term?” Nearly one in four (24%) chose 34–36 weeks, half chose 37–38 weeks, and the remaining quarter chose 39–40. Researchers also asked, “What is the earliest point in the pregnancy that it is safe to deliver the baby, should there be no other medical complications requiring early delivery?” More than half (52%) of the new mothers chose 34 to 36 weeks, while fewer than 10% chose 39–40 weeks. For neither question did women’s responses vary significantly by age, ethnicity, marital status, education, region of the country, or income.

The researchers did not report which women took childbirth education classes and whether responses were more accurate among women who did. But another research team has reported that childbirth classes that include specific content focusing on risks of elective induction are effective at reducing demand for such inductions. Now that hospitals face Joint Commission core quality measures for perinatal care that include refraining from elective deliveries prior to 39 weeks, the results of UnitedHealthcare’s survey strongly suggest that educating women about the risks of cutting a healthy pregnancy short will play an important role in helping hospitals comply.

2. In the current issue of Birth, a team of midwifery researchers report findings from a qualitative study of 10 top selling childbirth advice books. The researchers used discourse analysis to gauge such factors as how the woman’s role was portrayed, whether language emphasized risk, how birth settings and providers were described, how pain and coping strategies were discussed, and whether the books provided full disclosure of best scientific evidence. While a few books provided evidence-based information, normalized the process of birth, and situated the mother at the center of decision-making, others painted birth as scary, risky, foul, and debilitating, or reinforced messages that women should cede their power to doctors and modern medicine. The researchers conclude,

The U.S. medical and obstetrical community presents itself as practicing according to best scientific evidence. However, many of the books examined, 70 percent of which were endorsed, reviewed, and/or written by physicians, did not systematically present data to support or refute common maternity practices. Why? Does evidence counter or conflict with common obstetrical practice? Will women become ‘too’ demanding or make decisions for which they are deemed unqualified?

3. RH Reality Check just posted an interview with childbirth educator, Vicki Elson, whose documentary film, Laboring Under an Illusion, explores another way people in our culture learn about birth: on television. She presents 100 clips from sit-coms, “reality” birth TV shows, movies, and childbirth education videos to juxtapose real births with fake births and “let people make up their own minds.”

Vicki describes her impetus for making the movie:

I was doing a workshop for nurse-midwives at a local hospital when a particularly ghastly and unrealistic (and Emmy-winning) episode of “E.R.” came out. The midwives said their phones were ringing off the hooks because moms were scared that they could die like the lady on TV. Meanwhile, Murphy Brown was America’s liberated TV mom who could anchor the news and stand up to Dan Quayle. But in labor, she was wilted and powerless, except when she was strangling men by their neckties. I wanted my kids and their friends to grow up with realistic, nourishing imagery about the power of their bodies to do normal things like have babies. I was working with midwives Rahima Baldwin Dancy and Catherine Stone on a workshop called “Empowering Women in the Childbearing Year,” and we started collecting clips to show childbirth educators what they were up against from the culture. It’s still a struggle to compete with compelling but unrealistic imagery that sticks in people’s minds. I expanded on that project to write my master’s thesis 10 years ago, and when the kids grew up I finally got around to updating the project and putting it on DVD so it’s more useful and accessible.”

I’ve managed to miss Vicki’s presentation at two conferences I’ve attended and have not yet seen the film, but the trailer is delightful and Amie Newman’s interview at RH Reality Check is enlightening. I suggest you click on over.

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A Case of Statistical Malpractice? Predicting the Risk of Uterine Rupture

December 12th, 2009 by avatar

‘Tis the season for the Society for Maternal-Fetal Medicine to publish the abstracts for their forthcoming annual meeting. Every year around this time I receive the gift of an electronic Table of Contents alert for the Supplement to the American Journal of Obstetrics and Gynecology that lists conference sessions.  MFM doctors do interesting research, and their conference, which I have never attended, always has several sessions that look fantastic along with others that make me cringe (like a recent year’s session plugging this “exciting innovation“).

Nestled among the 800+ abstracts was one that I would put in the cringeworthy column, not for the focus of the research but for the complete mismatch between the reported findings and the researchers’ conclusions. [Emphasis mine]

Frequent epidural dosing is a marker for impeding uterine rupture in patients attempting vaginal birth after cesarean (VBAC)

Alison Cahill, Anthony Odibo, Jenifer Allsworth and George Macones
Washington University in St. Louis, St. Louis, Missouri

Objective
To estimate the association between epidural dosing and risk of uterine rupture in women attempting VBAC.

Study Design
A nested case-control study within a multicenter retrospective cohort of >25, 000 women with a prior cesarean was performed, comparing cases of uterine rupture to women without rupture (controls) while attempting VBAC. Extensive data extraction included all medications in 15-minute increments. In women who attempted VBAC with an epidural anesthetic, dose timing, frequency, and quantity were compared between cases and controls. Time-to-event analyses were performed to estimate the association between epidural dosing and risk for uterine rupture while accounting for duration of labor and confounding effects.

Results
Of 804 women in the nested case-control study; 504 (62.7%) had an epidural, with no statistical difference in epidural usage rates between cases and controls (70.4% v. 62.4%, p=0.09). Women who experienced uterine rupture were > 4 times more likely to require epidural dosing in the 60 minutes prior to delivery (aOR 4.1, 2.4 – 6.7, p <0.01). Cox-regression analysis revealed a dose-response relationship between number of doses in the final 90 minutes of labor and risk of rupture, after adjusting for prior vaginal delivery, and oxytocin exposure.

Conclusion
Clinical suspicion for uterine rupture should be high in women requiring frequent epidural dosing during a VBAC trial.

What’s the problem here?  This is a classic example of reporting the “hazard ratio” (e.g., “4 times more likely”) in lieu of the more appropriate statistics, which in this case would be the “positive predictive value”. It is indeed noteworthy that women destined to experience uterine ruptures self-administer more anesthesia in the minutes prior to the event, but should “clinical suspicion be high” every time a woman in a VBAC labor pushes the epidural button frequently? At least from the data reported in the abstract, the answer is: we have no idea.

To get an answer we need much more data. Specifically, we need to know:

  • how many women pushed the epidural button frequently
  • how many of them had a uterine scar rupture
  • how many women did not push the button frequently
  • how many of them had a uterine scar rupture

These data would help us calculate the sensitivity and specificity of epidural dosing in predicting uterine scar rupture, which in turn tell us the likelihood of a “false positive” (a woman requests frequent doses of epidural but does not have a scar rupture) and a “false negative” (a woman doesn’t request frequent epidural dosing but does have a scar rupture).

Sensitivity and specificity are especially important in predicting something that occurs rarely, such as uterine scar rupture in a VBAC labor. Reporting that something is “4 times more likely” could still be a small risk in absolute terms, if the baseline risk is low. In the case of VBAC, this kind of reporting could in fact be hazardous, because it is likely that many women and even many obstetricians overestimate the baseline risk of uterine scar rupture and of rupture-related morbidity and mortality.  So quadrupling it would falsely elevate risks even further. Let’s take for example statistics put forth by a spokesperson for the American College of Obstetricians and Gynecologists. In a letter to a mother who appealed to the College to make VBAC more accessible, he notoriously overestimated the risks.

In two percent of [VBAC labors] the result can be a rupture of the old scar. If this happens, then death of the baby is almost certain and death of the mother is probable. Even if the mother does not die, virtually 100% will lose their child bearing ability.

In this scenario, anything associated with a 4-fold increase in uterine rupture would result in 6 additional babies dying plus 6 additional mothers dying or needing hysterectomies for every 100 VBAC labors. Looking at these data, it’s easy to justify doing a cesarean when the woman begins asking for epidural top-ups even if top-up requests have a low predictive value.

But the uterine scar rupture rate is in fact 0.5-1%, and in only about 5% of ruptures is the baby likely to die. Maternal mortality is rarer still, and the likelihood of either maternal mortality or hysterectomy is actually higher with repeat cesarean surgery than it is with planned VBAC. Quadrupling these risks might result in 15 excess fetal/newborn deaths per 10,000 VBAC labors. This may still seem to be an unacceptable risk, but it’s nothing close to 6 per 100. In this scenario, it’s a little more difficult to justify going straight to a cesarean for every woman requesting more anesthesia.

I’ll give the researchers the benefit of the doubt. It is clear that they understand the distinction between relative risk and predictive value, since they’ve published papers on the topic before that appropriately concluded that obstetric variables poorly predict the likelihood of scar rupture. They may also have been severely limited by journal space constraints in preparing their abstract for publication. But I’ll call “statistical malpractice” on them for publishing a conclusion that suggests that the predictive value is high without providing any data to support it.

FYI, this topic should be familiar to anyone listening to the news lately, as false positive are at the crux of the debate about the new mammography guidelines. The New York Times ran a piece explaining concepts of risk and predictive value just last week, with the decidedly unsexy title, Mammogram Math. It’s a  great read for anyone who wants to know more about interpreting statistics about risk.

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Tracking Down Studies: Going Around Obstacles

December 9th, 2009 by avatar

While I’ve spent a lot of time teaching about databases and indexes, they certainly are not the only way you can track down studies. In this final installment of the tracking down studies part of the Understanding Research series, I’ll show you how you can track down studies in other ways.

Last May I read an interesting blog post on Teri Shilling’s blog.

pfbblog

She posted about some research she’d read about in a magazine. The study had found that attending a childbirth class was the only significant predictor of whether or not a woman was satisfied with her childbirth experience.

Naturally, I wanted to know more, and being the “go straight to the source” type, I wanted to see the actual study. Teri had listed a few key pieces of information:

Study author = Angelina Arcamore

Study author’s place of work = Villanova University

Teri’s source: CBEreporter article written my Marsha Rehms

I started by asking Teri what she knew.

Askteri

Next I tried doing a search in EBSCO and PubMed for the author. Nothing. Tried searching for  the key words “Childbirth Education” and “satisfaction”. A few results, but nothing like what I was looking for.

Did a general Google searches for “Angelina Arcamore”, “CBEreporter” and for “Marsha Rehms”. Nothing helpful there.

So my only remaining clue was Villanova University. I went to their web site:

villanova

I searched their site for “Arcamore” and got nothing. Then I tried “childbirth education” and got a single hit:

Villanovahit

And voila! I found the faculty bio page of Angelina Arcamone!

Arcamonebio

Notice her name is actually spelled “Arcamone” instead of “Arcamore”! Somewhere along the way, a letter got misread as an r instead of an n. Very easy mistake.

So then I go back and do EBSCO, PubMed and Google Scholar searches for the correctly spelled name.

Still no results.

But remember how the faculty bio page had an e-mail address on it? Well, I decided to write to her and ask about the study. Within 24 hours she responded with a very nice e-mail:

Arcamoneresponse

While I found the information she sent me to be helpful, I am looking forward to seeing her study published!

Did you like this step-by-step of how I tracked down this study? You can find more articles like this on my web site.  If you have a study you’re having trouble finding and would like me to give it a try, send me an e-mail andrea [at] lythgoes [dot] net and I just might do it here on Science & Sensibility!

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What SUVs Can Teach Us About Maternity Care

December 6th, 2009 by avatar

Twice last week, analogies between sport utility vehicles (SUVs) and the organization of our maternity care system came up in blog comment discussions. In a spirited discussion between Katharine Hikel and AcademicObgyn.com‘s Nicholas Fogelson on Hikel’s post, Disputed Territory, she proposed, “maybe it’s time to change from the SUV model to the compact hybrid…The ACOG hospital model is neither sustainable nor affordable.” In a thoughtful post about military terminology and philosophy in healthcare at e-Patients.net, again conversation turned to the American enhusiasm for SUVs.

Henci Goer and I decided it would be fun to share a sneak peak excerpt of our book, Obstetric Myths versus Research Realities, 2nd edition, due out late next year. With apologies to those who drive SUVs, here it is…

What SUVs Can Teach Us about Maternity Care
Excerpt from Goer, H. & Romano, A. (In Press)
Obstetric Myths versus Research Realities, 2nd Edition, The University of Michigan Press: Ann Arbor, MI.

A recent advertising campaign for a large sport utility vehicle (SUV) offers an excellent analogy to conventional thinking in maternity care. Parallel to the “just in case” approach of obstetric management, the ads acknowledge that the average SUV driver will hardly ever need the heft and power of an SUV, but the “one percent” chance of being caught in a blizzard or hurricane means the driver would be wise to own a vehicle that can safely navigate treacherous conditions. The SUV, the ads declare, is “built for the one percent.” Let us see how the flaws in this argument translate to maternity care.

SUV creative commons1

  • The technology that makes an SUV superior in severe adverse driving conditions provides no benefit to the driver 99% of the time because severe adverse driving conditions are rare. Likewise, the technology that can improve outcomes in very problematic pregnancies provides no benefit to most women and babies most of the time because these conditions are rare.
  • Most SUV drivers live in temperate climates, where the likelihood of a blizzard or similar natural disaster on any given day is extremely low. Likewise, most pregnant women are healthy and at low risk of experiencing a “natural disaster” during childbirth.
  • The driving conditions in which an SUV offers an advantage are usually predictable. Blizzards and hurricanes, for example, rarely take a driver completely by surprise. Likewise, we can often predict which women will develop complications in pregnancy or birth. Most pregnancy and labor complications develop slowly, giving plenty of time to avert them or access the resources needed to safely manage them.
  • Individuals and society as a whole expend resources to build, fuel, and maintain SUVs and to accommodate them on our roadways despite the fact that most people could drive smaller cars most of the time and be equally well off—or better off. Likewise, technology-intensive obstetric management is extremely costly and requires specialized staff resources and physical infrastructure to support it, despite the fact that a lower-technology approach with access to technology when it is indicated provides equivalent or better outcomes.
  • Although the SUV’s bigger size and greater weight offer some protection when collisions occur, these same characteristics make them more prone to accidents. The weight of the vehicle makes it more difficult to brake to avoid collisions and the higher center of gravity is responsible for more rollovers. The net effect is that SUVs may actually be more likely than smaller cars to be involved in serious or fatal accidents to drivers or passengers. Likewise, obstetric interventions can be beneficial in some circumstances, but their use frequently results in iatrogenic harm. The net effect is that women and infants often fare worse than if they had not been exposed to the intervention in the first place.
  • Some people choose an SUV because they genuinely need one for the road conditions under which they do most of their driving. In these cases, an SUV makes sense. Likewise, women who have medical problems or are likely to develop pregnancy or labor complications will benefit from intensified use of obstetric technology. These women are likely to seek out specialist care.
  • Although we can measure the degree to which weather or traffic conditions are poor and accidents more likely, this information cannot tell us which cars are destined to get into accidents or whether any individual accident will be minor or major. Similarly, screening tests (e.g., fetal surveillance, electronic fetal monitoring) and prenatal risk or candidacy for VBAC scoring systems have poor predictive value and lead obstetricians to over treat. They also fail to distinguish problems where intervention can help from problems where it cannot.
  • Most accidents are fender-benders that cause no more than minor harm no matter what kind of vehicle is involved. Likewise, most complications in pregnancy and birth are minor and will not result in any serious or long-term harm to mother or baby no matter what kind of care they receive.
  • Some accidents will cause major injury or death no matter what kind of vehicle is being driven. Likewise, some babies and even some mothers will suffer severe morbidity or die no matter what kind of care they receive. Even in the best-equipped hospitals with superbly qualified staff, in some cases, nothing can be done to prevent the worst from happening.

Midwives Deliver bumper sticker2

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