Risks, Values, and Decision MakingSurrounding PregnancyAnne Drapkin Lyerly, MD, MA, Lisa M. Mitchell, PhD, Elizabeth M. Armstrong, PhD, MPA,Lisa H. Harris, MD, PhD, Rebecca Kukla, PhD, Miriam Kuppermann, PhD, MPH,and Margaret Olivia Little, PhD

Assessing, communicating, and man-aging risk are among the most chal-

lenging tasks in the practice of med-icine and are particularly difficult inthe context of pregnancy. We analyzecommon scenarios in medical deci-sion making around pregnancy, fromreproductive health policy and clini-cal care to research protections. Wedescribe three tendencies in thesescenarios: 1) to consider the proba-bilities of undesirable outcomesalone, in isolation from womens val-ues and social contexts, as determi-native of individual clinical decisionsand health policy; 2) to regard anyrisk to the fetus, including incremen-tal risks that would in other contextsbe regarded as acceptable, as trump-ing considerations that may be sub-stantially more important to the well-being of the pregnant woman; and 3)to focus on the risks associated withundertaking medical interventionsduring pregnancy to the exclusion ofdemonstrable risks to both womanand fetus of failing to intervene.These tendencies in the perception,communication, and management ofrisk can lead to care that is neitherevidence-based nor patient-cen-tered, often to the detriment of bothwomen and infants.(Obstet Gynecol 2007;109:97984)

Assessing, managing, and effec-tively communicating risk areamong the most challenging tasksin the practice of medicine. A vari-ety of cognitive biases are well-documented: absolute and relativerisks are often confused, ranges ofrisk get falsely dichotomized into

binary categories of low risk andhigh risk, and information fram-ing can alter risk perception.13

Pregnancy is a particularly com-plex and charged setting in whichto reason about risk, involving as itdoes both woman and fetus. Thesecomplexities around risk presentespecially difficult challenges forobstetricians in their efforts to pro-vide optimal care for their patients.

In this article, we outline threepatterns in risk perception and rea-soning that affect medical decisionmaking around pregnancy. Using aspectrum of examples across repro-ductive health policy, clinical care,and research protections, we de-scribe three pervasive patterns:first, a tendency to regard probabil-ities of undesirable outcomesalone, in isolation from womensconcerns, values, and social con-texts, as determinative for policyguidelines; second, a tendency toregard any risk to the fetus, includ-ing incremental risks that would inother contexts be regarded as ac-ceptable, as trumping consider-ations that may be substantiallymore important to the pregnantwoman and her family; third, atendency to notice the risks associ-ated with medical interventionsduring pregnancy to the exclusionof demonstrable risksto bothwoman and fetusof not interven-ing. Sometimes these tendencieslead to guidelines and practices

From the Department of Obstetrics and Gynecology andTrent Center for Bioethics, Humanities, and History ofMedicine, Duke University Medical Center, Durham,North Carolina; Department of Anthropology, Univer-sity of Victoria, Victoria, British Columbia, Canada;Office of Population Research, Princeton University,Princeton, New Jersey; Department of Obstetrics andGynecology, University of Michigan Health System,Ann Arbor, Michigan; Department of Philosophy, Car-leton University, Ottawa, Ontario, Canada; Depart-ment of Obstetrics, Gynecology & Reproductive Sciencesand Medical Effectiveness Research Center, School ofMedicine, University of California, San Francisco,California; and the Kennedy Institute of Ethics andDepartment of Philosophy, Georgetown University,Washington, DC.

The authors are the Obstetrics and Gynecology RiskResearch Group.

Supported in part by the Josiah Charles TrentFoundation, Duke University; the Greenwall Foun-dation; the Robert Wood Johnson Foundation;Georgetown University; the University of California,San Francisco, Department of Obstetrics, Gynecol-ogy, & Reproductive Sciences and Center for Excel-lence in Womens Health; Carleton University; theCenter for Health and Wellbeing at Princeton Uni-versity; the Social Science and Humanities ResearchCouncil of Canada and the University of MichiganInstitute for Research on Women and Gender.

The views expressed in this article are solely those ofthe authors and do not represent those of any of thesponsoring organizations.

Presented as a poster at the American College ofObstetricians and Gynecologists 54th Annual Clin-ical Meeting, May 610, 2006, Washington, DC.

Corresponding author: Miriam Kuppermann, De-partment of Obstetrics, Gynecology, & ReproductiveSciences, UCSF, 3333 California Street, Suite 335,San Francisco, CA 94143-0856; e-mail:kuppermannm@obgyn.ucsf.edu.

2007 by The American College of Obstetriciansand Gynecologists. Published by Lippincott Williams& Wilkins.ISSN: 0029-7844/07

VOL. 109, NO. 4, APRIL 2007 OBSTETRICS & GYNECOLOGY 979

whose restrictive nature may beunwarranted; other times, the pre-ponderance of evidence points to aclearer course of action than is cur-rently acknowledged. Together,the examples that follow highlightthe particular forms of selectiveperception and problematic rea-soning that can manifest them-selves in pregnancy. Although of-ten rooted in the best of intentions,these tendencies can lead to clinicalcare that is neither evidence-basednor patient-centered.

TENDENCY TO CONSIDERPROBABILITIES OUT OF THECONTEXT OF PATIENTVALUESConsider, first, prenatal testingguidelines that focus solely onprobabilities. Invasive prenataltesting (amniocentesis and chori-onic villus sampling) for chromo-somal disorders is routinely offeredonly to pregnant women who willbe at least 35 years old at deliveryor who have been found via serumor ultrasonographic screening tohave a risk of fetal chromosomalanomaly equal to or greater thanthat of a 35 year old. This age- andrisk-based threshold for testing hasbeen endorsed by published guide-lines4,5 and used as a criterion forcoverage by public and private in-surance.6 With the advent of first-trimester screening for chromo-somal anomalies,7 the age-basedcriterion for testing became furtherentrenched: younger women arereferred for invasive testing only iftheir posttest probability of carry-ing an affected fetus is at least ashigh as the average 35-year-oldwoman.

Although widely accepted, con-temporary policies that index thethreshold for invasive testing onthe average risk present at age 35 infact rest on a questionable ratio-nale. In fact, the 2007 AmericanCollege of Obstetricians and Gyne-

cologists (ACOG) Practice Bulletinaddressing screening for fetal chro-mosomal abnormalities called intoquestion this rationale in its groundbreaking policy statement indicat-ing that all women, regardless ofage, should have the option of in-vasive testing.8 The longstandingthreshold reflects neither a suddenrise in risk at age 35, as patientsoften believe, nor the level of risk atwhich diagnostic testing becomescost-effective.9 Instead, it marks thepoint at which the probability ofhaving a child with Down syn-drome is equal to that of a proce-dure-related miscarriage.10 But ifguidelines equate these two out-comes, women do not. Empiricalstudies show that women vary, andvary substantially, in their assess-ments of these outcomes.11 Many

women regard one but not theother outcome as catastrophic, andwomen differ on which outcomemight so count: to a 41-year-oldnullipara with recurrent first-tri-mester pregnancy loss, it mightwell be the procedure-related mis-carriage; to a 28 year old with twosmall children, it might be the birthof a child with Down syndrome.Further, womens decisions aboutwhether to test are shaped by nu-merous factors in addition to theirevaluation of these two outcomes,including cultural meanings, socialcircumstances, religious beliefs,and attitudes toward abortion.1214

The implementation of the age 35threshold for prenatal testing, inshort, is based on equating whatare, from the patients perspective,two very different outcomes, as

well as on the unsubstantiated as-sumption that those two outcomesare the only ones centrally salientto decision making.

Guidelines that fail to accountfor the range of womens valuescarry heavy costs. Risk-based in-dexing ends up denying diagnostictesting to individuals whose prefer-ences indicate they would benefitfrom it15: women under 35 whowant testing without screening pos-itive must first persuade their phy-sicians to order the test, then eitherpay for the procedure or attempt toqualify for coverage citing mentalhealth diagnoses such as maternalanxiety. It also unintentionallypromotes intervention amongwomen for whom risks of both theprocedure and the knowledge itentails outweigh the benefits,13 be-cause those designated officially atrisk face heightened anxieties, andwomen over 35 who decline inva-sive testing may be regarded byothers as irresponsible.16

Here, then, we see the first pat-tern: a tendency to regard numeri-cal risk estimates alone, in isolationfrom womens values and socialcontexts, as determinative of indi-vidual clinical decisions and healthpolicy. By their very nature, ofcourse, guidelines restrict choiceand limit the extent to which carecan be determined by individualvalues. But when those values varywidely and deeply among the verypeople whose lives will be mostaffected by the outcomes at issue,as they do with prenatal testing, theappropriateness of clinical algo-rithms purporting to set out theproper ratio of outcomes is opento question. Rather than using abright line risk demarcation todetermine who is offered invasivediagnostic testing, it may be reason-able to regard such testing as anoption prenatal care providerscould raise with each patient, to bediscussed in the context of the pa-

Pregnant women deserve

care that is both evidence-

based and patient-centered.

980 Lyerly et al Risk Communication Challenges OBSTETRICS & GYNECOLOGY

tients own values, preferences, andpriorities.

TENDENCY TO CONSIDERELIMINATION OF FETAL RISKAS PARAMOUNT INSELECTED CIRCUMSTANCESTake, next, the heightened concernabout fetal risk in the context ofvaginal birth after cesarean deliv-ery (VBAC)a risk that has notbeen the subject of significant con-troversy in primary vaginal deliv-ery. After several well-publicizedreports of complications of trials oflabor after previous cesarean,17,18

ACOG issued a practice bulletinstating that VBAC should be of-fered only in situations in which aphysician capable of performingemergency cesarean delivery, ananesthesiologist, and personnel foremergency delivery are immedi-ately available throughout activelabor.19 Reports indicate thatwomen desiring VBAC have sincefound it increasingly difficult to at-tempt delivery in their preferredmode. Some hospitals now prohibitVBAC,20 and some professional li-ability insurance companies willnot cover physicians who attendvaginal deliveries after previous ce-sareans, even when they do so inthe recommended setting.21

The question is whether evidencesupports these restrictive policies.The central concerns driving VBACrestrictions are the risks of perinataldeath and of uterine rupturerelatedhypoxic brain injury. According toACOGs practice bulletin onVBAC,restrictive guidelines are justified spe-cifically because uterine rupture canbe catastrophic.19 Although theseoutcomes are clearly devastating,careful reflection on their incidence,and the broader context of risk andpregnancy, complicates the matter ofwhether such restrictions are war-ranted. First, although it is true thatwomen undergoing VBAC face aslightly higher risk of perinatal death

than women undergoing cesareandelivery, their risk of perinatal deathis in fact the same as for womenundergoing primary vaginal delivery.In a study of more than 300,000singleton births, the risk of perinataldeath associated with a trial of vagi-nal birth after cesarean delivery wascomparable to that of nulliparas inlabor.22 Although perinatal death,when it occurred, was more likely tobe a result of mechanical factors inwomen undergoing VBAC, theoverall rate of perinatal death for anyreason was not different in womenundergoing VBAC compared withnulliparous women in labor. Yet pri-mary attempted vaginal delivery inthe absence of particular risk factorsis, to put it mildly, widely regardedas a reasonable option. Given com-parable perinatal death rates be-tween VBAC and primary vaginaldelivery, a problematic double stan-dard underlies VBAC restrictionsand calls into question theirjustification.

Although rates of delivery-re-lated perinatal death are indistin-guishable between VBAC and pri-mary vaginal delivery, there is agenuine differential in the rate ofuterine rupturerelated hypoxic-ischemic encephalopathy. Suchperinatal morbidity is indeed dev-astating. It is also extremely rare. Ina recent large prospective study,the probability of this outcome was0.00046 in infants whose mothersunderwent a VBAC trial at termcompared with no cases in infantswhose mothers underwent repeatcesarean delivery.23 If we couldeliminate this outcome at no cost,then of course we should, but elim-inating the possibility of uterinerupturerelated hypoxic brain in-jury comes at a price of other con-siderations that may be salient forwomen and their families. Womenhave all sorts of important and le-gitimate reasons for preferring onemode of delivery to another. Just as

repeat cesarean may be an impor-tant option for some women,VBACmay be an important optionfor many others. For example, awoman with previous complica-tions from a cesarean delivery maydecide she never again wants tocare for an open abdominal woundand a newborn at the same time, ora woman who plans to have severalchildren may reasonably want toavoid the increased morbidity asso-ciated with multiple abdominal sur-geries.24 More broadly, manywomen prefer vaginal delivery asthe method that will help theirbirths be manageable and mean-ingful events within the circum-stances of their lives and families.

Although deciding when it isreasonable to take actions thatcarry very small risk of a very badoutcome is challenging, it is alsosomething we do in everyday lifeincluding in the context of preg-nancy. In decisions about mode ofdelivery, as elsewhere in life, elim-inating risk comes at a cost. In thecontext of VBAC restrictions, itcomes at the particularly dear costof considerations that may matterdeeply to women and theirfamilies.

Here, again, we see a tendencyto regard probabilities alone asgrounding unequivocal recommen-dations out of the context of thebroader factors that give those esti-mates their meaning. Added here isa second pattern: a tendency topursue zero risk to the fetus, inde-pendently of the absolute size ofthe risk, of competing consider-ations, or of recognition that fetalrisk exists in other acceptable con-texts. Reducing perinatal morbid-ity and mortality is a critical goal.But there is an irreducible elementof risk in pregnancy and childbirth,no less than in life generally. Thus,pursuit of absolute zero risk to thefetus in clinical care or health pol-icy is not only quixotic,25 it is dis-

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proportionate to how we thinkabout risk elsewhere, including inthe treatment of born children.26

Further, we recognize as legitimatea myriad of choices made by preg-nant women in other contexts thatcarry a small risk of significant fetalmorbidityranging from daily taskssuch as driving a car27 to living in acity with high levels of air pollu-tion.28 It is the physicians obliga-tion not to eliminate risk, but to helppatients weigh risk, benefit, andpotential harm, informed by bestscientific evidence and guided by apatient-centered ethic. Rather thanusing directive criteria for womenapproaching labor after prior cesar-ean, it may be reasonable to regardboth VBAC and repeat cesarean asprudent options that can be en-dorsed in good conscience.

TENDENCY TO NOTICERISKS OF INTERVENING TOTHE EXCLUSION OF RISKSOF NOT INTERVENINGWith both prenatal testing andVBAC, patterns of risk perceptionand reasoning may overly narrowour sense of what constitute reason-able options. We turn now to twocases when it may be appropriateto be more directive regarding op-tions for pregnant women in healthpolicy and clinical care.

During pregnancy, women con-tinue to have health needs that areunrelated to their obstetric condi-tion. But attending to those needshas often proved challenging, withtendencies to focus on the risks ofintervening to the exclusion of risksof not intervening. Worries aboutfetal vulnerability, understandablein their own right, can end uplooming unduly, in ways that workto the detriment not only of preg-nant women, but often, ironically,the fetuses they carry.

Consider, for instance, radio-logic imaging studies for diagnosisin pregnant women. Consulting

physicians, radiologists, and tech-nologists are often reluctant to or-der or perform such imaging inpregnant women even in acute sit-uations, such as threatened appen-dicitis or trauma, out of concern forpossible teratogenic effects.29 Thishesitancy can lead to additional,often time-consuming, consulta-tions with obstetricians and extraconsent documentation from preg-nant women; it has also led to casesof radiologists outright refusal toimage.30

Reluctance to perform radio-logic tests, however, is nearly al-ways unfounded. As the AmericanCollege of Radiology affirms,31

well-documented animal and hu-man data indicate that the dose ofionizing radiation from radiologicprocedures, including plain filmsand abdominal or pelvic computedtomography scans with contrast,yields no increase in the risk ofcongenital malformations, growthrestriction, or pregnancy loss.32

Further, the existence of a link be-tween diagnostic radiation andchildhood leukemia, although of-ten raised as a concern by radiolo-gists and patients alike, is highlycontroversial, but if it exists, is ex-tremely small.33 Fetal radiation ex-posure from a chest X-ray per-formed on a pregnant woman isroughly equivalent to that from atranscontinental flight,34 and imag-ing resisted during pregnancy iswidely accepted for indicated useon premature infants, born as earlyas 23 weeks.35

Delayed diagnosis in a criticalcare setting exacts heavy costs.36

Septicemia from an undiagnosedruptured appendix is good for nei-ther woman nor fetus; indeed,some estimate a fetal loss rate ofless than 2% with an unrupturedappendix versus more than 30%after perforation.37 For some radi-ologists, reluctance is based on fearof legal liability if a woman who

has been imaged delivers an anom-alous baby.32,38,39 But errors ofomission can also lead to malprac-tice suitsfetal loss is also a vividbasis for litigation. More pointedly,given the preponderance of evi-dence, the slight risk of litigation isone that should be shouldered forthe responsible conduct of medi-cine. Obstetricians often find them-selves in the ironic position of re-minding other providers that,under a wide variety of circum-stances, best evidence supportstreating a pregnant patient thesame way as any other patient.

Here we see a third tendency: toattend to the risks of interveningout of proportion to the clear risks,to both woman and fetus, of failingto intervene. At the end of the day,assessment of any intervention iscomparative in nature; it is incom-plete if made without consideringthe risks of the alternatives.

This last tendency is notablypervasive. As providers who carefor pregnant women are all tooaware, patients themselves are of-ten prone to its selectivity, haltingmedications that are in fact criticalfor both maternal and fetal well-being.40,41 Women with severeasthma, for example, sometimesstop using their medications out offear of the harm it may cause theirfetuses. Halting medication can bea dangerous course for the woman;poorly controlled asthma places apregnant woman at higher risk ofhypertension, preeclampsia, anduterine hemorrhage.42 Moreover, itis risky for the fetus. Poorly con-trolled asthma is associated withintrauterine growth restriction, pre-maturity, and low birth weight;women with asthma well con-trolled by medication, in contrast,have perinatal outcomes as good ascomparable groups without asth-ma.42 As with others weighing risksin reproductive decision making,patients may need reminding that,

982 Lyerly et al Risk Communication Challenges OBSTETRICS & GYNECOLOGY

often, the best way to ensure thehealth of the fetus is to ensure thehealth of the pregnant woman.40

Perhaps most disturbingly, thetendency also has profoundly com-promised the evidence base formedical decision making in preg-nancy. Although we have mademuch progress on the inclusion ofnonpregnant women in clinical tri-als, thoughtful discussion of how toreason about research participationand pregnancy has lagged far be-hind. Despite an Institute of Medi-cine report recommending thatpregnant women not be summarilyexcluded from research proto-cols,43 many researchers and insti-tutional review boards continue toregard pregnancy as a virtually au-tomatic cause for exclusion, regard-less of the actual potential a givenintervention holds for fetal harm orthe costs of exclusion to womenand fetuses alike.

Consider an example from cur-rent international acquired immu-nodeficiency syndrome (AIDS) re-search. Vaginal microbicides havebeen identified as a promisingmeans for women in developingcountries to protect themselvesfrom sexual transmission of humanimmunodeficiency virus (HIV).44

Microbicides are compounds thatcan be applied inside the vagina orrectum that, if proven effective,would prevent sexually transmittedinfections including HIV. TheWorld Health Organization hascited the importance of their poten-tial utility as a low-cost preventiveoption that women can control andthat would not require cooperationof a sexual partner. High preg-nancy rates in study populationshave been accompanied by in-creased efforts to exclude pregnantwomen and to terminate enroll-ment for participants who do be-come pregnant (Raymond E. Issuesrelated to pregnancies in microbi-cide effectiveness trials. Microbi-

cides Conference. April 2326,2006; Capetown, South Africa). Al-though undoubtedly motivated bysafety concerns, exclusionary poli-cies may well do more harm thangood for maternal and child healthin Africa. Animal studies have notshown adverse effects of microbi-cides on fetal development, and thevaginal products do not seem to besystemically absorbed.45 Morepointedly, any possible teratogenicrisk from the gel must be consid-ered in the context of a very clear,real, and life-threatening risk thatmicrobicides aim to prevent,namely, maternal and fetal expo-sure to HIV infection. Further,given that pregnant women willcertainly be among the consumersof microbicides if they prove effec-tive, reassurance of the productsefficacy, as well as safety, would beuseful. Given that pregnancy is amarker of unprotected heterosex-ual activity, understanding the ef-fects of a medication aimed at mit-igating the risks of such exposure isparticularly important for thisgroup.

TOWARD EVIDENCE-BASEDAND PATIENT-CENTEREDDECISION MAKINGAROUND PREGNANCYPregnant women deserve care thatis both evidence-based and patient-centered. Rather than reinforce thedistortions of risk that do such dis-service to pregnant women andtheir fetuses, providers and policy-makers can play a key role in help-ing to overcome them. They cando so, first, by acknowledging therange of values that pregnantwomen and their families bring todecisions around pregnancy anddelivery, and identifying, where ap-propriate, a range of well-consid-ered options, allowing women tomake decisions in the context oftheir own priorities and life circum-stances. They can do so, second, by

basing recommendations andguidelines on the full profile of risksin the range of comparable clinicalscenarios and also by including thelegitimacy of maternal well-beingas a consideration, both for its ownsake and its importance to fetalwell-being. They can do so, third,by underscoring the importance ofexpanding our evidence base sothat patients and providers canmake informed decisions that doinvolve the weighing of risk duringpregnancy. Most of all, they can doso, not by suspending the usualmodes of analysis when confrontedwith pregnancy, but by giving thesame careful, responsible, andcomprehensive assessment wehope for in all of medicine.

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