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Gestational Diabetes Mellitus DiagnosedWith a 2-h 75-g Oral Glucose ToleranceTest and Adverse Pregnancy OutcomesMARIA I. SCHMIDT, MD, PHD1

BRUCE B. DUNCAN, MD, PHD1

ANGELA J. REICHELT, MD, PHD2

LEANDRO BRANCHTEIN, MD, PHD2

MARIA C. MATOS, MD, PHD2

ADRIANA COSTA E FORTI, MD, PHD3

ETHEL R. SPICHLER, MD, PHD4

JUDITH M.D.C. POUSADA, MD, PHD5

MARGARETH M. TEIXEIRA, MD, MS6

TSUYOSHI YAMASHITA, MD7

FOR THE BRAZILIAN GESTATIONAL DIABETESSTUDY GROUP

OBJECTIVE To evaluate American Diabetes Association (ADA) and World Health Orga-nization (WHO) diagnostic criteria for gestational diabetes mellitus (GDM) against pregnancyoutcomes.

RESEARCH DESIGN AND METHODS This cohort study consecutively enrolledBrazilian adult women attending general prenatal clinics. All women were requested to under-take a standardized 2-h 75-g oral glucose tolerance test (OGTT) between their estimated 24thand 28th gestational weeks and were then followed to delivery. New ADA criteria for GDMrequire two plasma glucose values 5.3 mmol/l (fasting),10 mmol/l (1 h), and8.6 mmol/l(2 h). WHO criteria require a plasma glucose 7.0 mmol/l (fasting) or 7.8 mmol/l (2 h).Individuals with hyperglycemia indicative of diabetes outside of pregnancy were excluded.

RESULTS Among the 4,977 women studied, 2.4% (95% CI 2.02.9) presented with GDMby ADA criteria and 7.2% (6.57.9) by WHO criteria. After adjustment for the effects of age,obesity, and other risk factors, GDM by ADA criteria predicted an increased risk of macrosomia(RR 1.29, 95% CI 0.732.18), preeclampsia (2.28, 1.224.16), and perinatal death (3.10,1.426.47). Similarly, GDM by WHO criteria predicted increased risk for macrosomia (1.45,1.06 1.95), preeclampsia (1.94, 1.223.03), and perinatal death (1.59, 0.862.90). Of women

positive by WHO criteria, 260 (73%) were negative by ADA criteria. Conversely, 22 (18%)women positive by ADA criteria were negative by WHO criteria.

CONCLUSIONS GDM basedon a 2-h 75-g OGTT definedby either WHO orADA criteriapredicts adverse pregnancy outcomes.

Diabetes Care 24:11511155, 2001

Gestational diabetes mellitus (GDM)is defined as glucose intolerance ofvariable severity with onset or first

recognition during pregnancy (1,2). In

the U.S., the definition of GDM has beenlargely based on pregnancy-specific crite-ria applied to a 3-h 100-g oral glucosetolerance test (OGTT). In contradistinc-

tion, World Health Organization (WHO)panels have adopted in pregnancy thesame diagnostic criteria applied to a 2-h75-g OGTT in nonpregnant individuals(24).

Although the American Diabetes As-sociation (ADA) still recommends a 3-h100-g OGTT for the diagnosis of GDM, ithas recently included in its recommenda-tions the use of a 2-h 75-g OGTT. Thesame fasting, 1-h, and 2-h diagnostic cutpoints are used in both tests. However,

for the 2-h test, two of three abnormalvalues are required for diagnosis insteadof the two of four required for the 3-h test(1,5).

A recent WHO panel, although ingeneral maintaining previous diagnosticrecommendations, now characterizesGDM as the joint category of diabetesand impaired glucose tolerance (fastingglucose 7.0 mmol/l or 2-h glucose7.8 mmol/l) (2).

The predictive ability of these newcriteria for the 2-h 75-g OGTT in terms ofpregnancy outcomes has been investi-gated little, particularly in cases not meet-ing the criteria for diabetes outside ofpregnancy. Thus, the objective of this re-port is to evaluate the new WHO and

ADA criteria for GDM by characterizingtheir ability to predict which pregnancieswill suffer macrosomic birth, preeclamp-sia, and perinatal death.

RESEARCH DESIGN AND

METHODS The Brazilian Gesta-tional Diabetes Study is a cohort studyconducted in general prenatal care clinics

of the National Health Service in six Bra-zilian state capitals: Porto Alegre, SaoPaulo, Rio de Janeiro, Salvador, Fortaleza,and Manaus. Local institutional ethiccommittees approved the study protocol,and patients consented to participate afterbeing informed about the nature of thestudy.

We enrolled women20 years of agebetween their 20th and 28th gestationalweek if they had a negative history of di-abetes outside of pregnancy. All womenresponded to a structured questionnaire,

From the 1Department of Social Medicine, School of Medicine, Federal University of Rio Grande do Sul,Porto Alegre; the2Postgraduate Program in Clinical Medicine,Federal Universityof Rio Grande do Sul, Porto

Alegre; the 3Department of Clinical Medicine, School of Medicine, Federal University of Ceara, Fortaleza,Ceara; the 4Department of Obstetrics and Gynecology, Instituto Fernandes FigueiraOswaldo Cruz Foun-dation, Rio de Janeiro; the 5Department of Medicine, Medical School, Federal University of Bahia, Salvador,Bahia; the 6Department of Medicine,Federal University of Amazonas, Manaus, Amazonas; and the 7Hospitaldos Servidores Publicos do Estado de Sao Paulo, Sao Paulo, Brazil.

Address correspondence and reprint requests to Maria Ines Schmidt, Av. Luiz Manoel Gonzaga, 630/8,Porto Alegre, RS 90470-280 Brazil. E-mail: [email protected].

Received for publication 12 October 2000 and accepted in revised form 28 February 2001.Abbreviations: ADA, American Diabetes Association; GDM, gestational diabetes mellitus; OGTT, oral

glucose tolerance test; RR, relative risk; WHO, World Health Organization.A table elsewhere in this issue shows conventional and Systeme International (SI) units and conversion

factors for many substances.

E p i d e m i o l o g y / H e a l t h S e r v i c e s / P s y c h o s o c i a l R e s e a r c h

O R I G I N A L A R T I C L E

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underwent standardized anthropometricmeasurements, and were invited to do a2-h 75-g OGTT between their 24th and28th gestational week. They were thenfollowed through delivery and duringthe in-hospital postpartum period viachart review using a common structuredprotocol.

The OGTT used standard procedures(4). Briefly, we administered a 75-g anhy-drous glucose load after a 12- to 14-h fastand obtained fasting, 1-h, and 2-h sam-ples from an antecubital vein. We col-lected samples in tubes containingfluoride and kept them at 4C until cen-trifugation up to 2 h later. Plasma mea-surements were performed with glucoseoxidase methods (6), the coefficient ofvariation being 5%.

GDM was defined according to ADAs

new recommendations for the 2-h 75-gOGTT as at least two values greater than afasting glucose of 5.3 mmol/l, a 1-h glu-cose of 10 mmol/l, or a 2-h glucose of 8.6mmol/l (1). It was additionally defined bycurrent comparatively less stringent

WHO criteria (fasting7.0mmol/l or 2-h7.8 mmol/l) (2).

We defined macrosomia as a birthweight at or above the gestational agespecific (by week) 90th percentile of thestudy sample. The 90th percentile values,derived from gestational weekspecificfrequency tables of birth weight, were asfollows: for week 35, 3,425 g; week 36,3,500 g; week 37, 3,590 g; week 38,3,700 g; week 39, 3,790 g; week 40,3,920 g; week 41, 4,040 g; week 42,4,200 g; and week 43, 4,080 g. Perinataldeath was defined by fetal loss of1kgorwith estimated gestational age 28weeks, or by an early neonatal death (upto 7 days). Preeclampsia (or eclampsia),ascertained through chart review, wasclassified according to the National HighBlood Pressure Education Program

Working Group (7) as hypertension after

the20th week of gestation associated withproteinuria or convulsions, regardless ofwhether it was of new onset or superim-posed upon chronic hypertension. Wecalculated BMI using reported prepreg-nancy weight and then grouped valuesinto nutritional categories according tothe 1997 WHO recommendations (8).

We defined gestational age according tohierarchical criteria based on four clinicalexaminations: for 52% of the sample, ul-trasound before week 26; for 15%, ultra-sound after week 26 consistent with

neonatal age estimation or last menstrualperiod; for 23%, reported last menstrualperiod consistent with neonatal age esti-mation or uterine height; and for the re-maining 10%, neonatal age estimation,ultrasound after week 26, uterine height,or last menstrual period.

The study was observational in na-ture. Decisions concerning managementof hyperglycemia were left to the clinical

judgment of the patients attending obste-tricians. Information concerning insulinand diet therapy was obtained from chartreview.

Of the initial 5,564 consecutivewomen enrolled from May 1991 through

August 1995, 4,998 (90%) concluded thescheduled OGTT. To focus risk assess-ment on the range of hyperglycemia thatoutside of pregnancy is considered im-

paired glucose tolerance, we excluded 21women from the analyses who met diabe-tes criteria (fasting glucose 7.0 mmol/lor 2-h glucose 11.1 mmol/l). The totalnumber of women available for specificoutcome analyses varied, as detailed inRESULTS.

Because macrosomia and preeclamp-sia were not rare events, the crude andadjusted odds ratios estimated by logisticregression were transformed to relativerisks (RRs) (9) for all outcomes. We cal-culated the population-attributable frac-tion using the following (10):

A

M

OR 1

OR

where A equals the number of outcomesamong individuals with GDM, M equalsthe total number of outcomes, and ORequals the adjusted odds ratio for the as-sociation between GDM and outcome.

RESULTS Table 1 shows the char-acteristics of the 4,977 women who com-pleted the 2-h 75-g OGTT.

GDM based on ADA criteria was di-agnosed in 119 (2.4%; 95% CI 2.02.9)women. Using WHO criteria, GDM wasdiagnosed in 357 women (7.2%; 6.57.9). Figure 1 illustrates the overlap inGDM classification obtained by these twocriteria; only 97 cases (81% of total ADAcases and 27% of total WHO cases) werepositive by both criteria. Women classi-fied only by WHO criteria had lower fast-ing (5.0 vs. 5.7 mmol/l; P 0.001) buthigher 2-h (8.3 vs. 6.5 mmol/l; P 0.001) plasma glucose values than

women classified only by ADA criteria.They were also younger (29.5 vs. 32.3years; P 0.03), shorter (154.2 vs. 157.6cm; P 0.02), and leaner (24.2 vs. 26.3kg/m2; P 0.03). No statistically signifi-cant differences between these twogroups were observed regarding frequen-cies of macrosomia (ADA only, 17.7% vs.

WHO only, 14.6%), preeclampsia (4.8

Figure 1Overlap of cases of GDM as diag-nosed by the ADA and WHO criteria for a 2-h75-g OGTT.

Table 1Characteristics of the 4,977 adultpre gnant women com ple ting a 2-h 75- g

OGTT in the Brazilian Study of GestationalDiabetes, 19911995

Ethnicity

White 2,234 (44.9)Mixed 2,042 (41.1)

Black 679 (13.6)

Other 21 (0.4)

Prepregnancy weight status

Underweight (BMI 18.5

kg/m2)

276 (5.8)

Normal (18.5 kg/m2 BMI

25.0 kg/m2)

3,151 (66.1)

Preobese (25.0 kg/m2

BMI 30 kg/m2)

1,024 (21.5)

Obese (BMI 30.0 kg/m2) 314 (6.6)

Education (years)

8 2,181 (44.0)

811 2,298 (46.2)11 486 (9.8)

Short stature (150 cm) 832 (16.8)

Age (years)

2024 1,649 (33.1)

2529 1,580 (31.8)

30 1,748 (35.1)

Parity

0 1,360 (30.6)

1 1,486 (33.4)

2 844 (19.0)

3 748 (15.0)

Data are n (%). The variation in category totals re-

sults from missing information relating to the char-acteristic in question.

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vs. 5.0%), or perinatal death (5.9% [1/17]vs. 2.6% [6/229]).

To investigate the association of GDMwith macrosomia, we analyzed data from3,925 women (79% of those complet-ing the OGTT). Not included were 546women giving birth to twins or withoutfollow-up, 214 with incomplete data oncovariates, 92 with unrecorded birthweight, 198 delivering before 35 weeksgestation, and 2 placed on insulin. Wom-en included were similar to the 1,052women not included with regard to age,ethnicity, educational level, nutritionalstatus, and parity. Of the included wom-en, 9.7% (379/3,925) gave birth to mac-rosomic infants.

Table 2 shows that GDM, regardlessof the criteria used to classify it, predictedan 5070% greater risk of delivering amacrosomic infant, although when classi-fied by ADA criteria, the increased riskwas not statistically significant. For WHOcriteria, a statistically increased risk per-

sisted, although somewhat reduced (RR1.45), after adjustment for center, ethnic-ity, neonatal sex, maternal height, age,prepregnancy BMI, and weight gain up toenrollment. With this adjustment, 4%of the macrosomic infants observed couldbe attributed to GDM defined by WHOcriteria, but 1% when defined by theless prevalent ADA GDM criteria.

To investigate the association of GDMwith preeclampsia, we analyzed data from4,572 women (92% of those completingthe OGTT). Not included were the 175

women without follow-up and the 230with incomplete data on covariates. Noneof the women remaining received insulintreatment. Women included were similarto the 405 women not included with re-gard to age, educational level, and nutri-tional status; women studied were morefrequently white (46 vs. 35%) and nullip-arous (31 vs. 24%). Among women stud-ied, 145 (3.2%) developed preeclampsia,with 7 being cases of eclampsia and 27cases of preeclampsia superimposed onchronic hypertension.

Table 2 shows that GDM was associ-ated with a two to three times greater riskof preeclampsia.After adjustment for cen-ter, ethnicity, maternal height, parity, ed-ucational level, age, prepregnancy BMI,and weight gain to enrollment, statisti-cally significant RRs of 2.28 for ADA and1.94 for WHO criteria were present. Withthis adjustment, 5% of the preeclamp-sia observed could be attributed to GDMas defined by ADA and 8% to the more

prevalent GDM by WHO criteria.To investigate the association of GDM

with perinatal mortality, we analyzed datafrom 4,216 women (85% of those com-pleting the OGTT). Not included were 4women with abortions (fetal loss before28 weeks), 547 giving birth to twins orwithout follow-up, and 210 with incom-plete data on covariates. None of the re-m a i n i n g w o m e n r e c e i v e d i n s u l i ntreatment. The 4,216 women includedwere similar to the 761 women not in-cluded with regard to age, educational

level, nutritional status, and parity;women studied were more frequentlywhite (46 vs. 40%). A total of 102 (24/1,000) perinatal deaths occurred, with 68(16/1,000) being fetal deaths and 34 (8/1,000) early neonatal deaths. There were13 deaths occurring in the 331 GDMwomen (WHO or ADA criteria), with 7(21/1,000) being fetal and 6 (18/1,000)early neonatal. Malformation was notedin only 1 of these 13 deaths.

Table 2 shows that women classifiedas having GDM based on ADA criteriapresented an approximately three timesgreater risk of a perinatal death. Increasedrisk (RR 3.10, 95% CI 1.426.47) wasmaintained after adjustment for center,ethnicity, maternal height, parity, educa-tional level, age, prepregnancy BMI, andweight gain to enrollment. With this ad-

justment,5% of theperinatal deathsob-served could be attributed to ADA-defined GDM. Classification based on

WHO criteria was less predictive of peri-natal death (RR 1.66; 95% CI 0.912.96).However, because WHO-defined GDMwas more prevalent, the percentage ofperinatal deaths (4.5%) attributable toGDM so-defined was similar to thatattributable to GDM defined by ADAcriteria.

Given the less than complete overlapof GDM cases diagnosed by the two crite-ria, we also assessed increased risks ofmacrosomia, preeclampsia, and perinataldeath associated with a diagnosis of GDMby only one of the two criteria against anegative diagnosis for both. Women diag-nosed only by WHO criteria (n 260)had a crude RR for macrosomia of 1.72(95% CI 1.22.4), of 1.75 (1.03.1) forpreeclampsia/eclampsia, and of 1.1 (0.52.6) for perinatal death. Crude RRs fordiagnosis only by ADA criteria (n 22)were 1.9 (0.75.4), 1.7 (0.211.3), and2.6 (0.417.4), respectively.

Because we detected considerably

more cases (357 vs. 119) of GDM usingWHO criteria versus ADA criteria, we alsodetected 3.5 times more (45 vs. 13) sub-

jects with GDM who later delivered mac-rosomic infants with WHO criteria.Similarly, we detectedtwo times more (23vs. 12) cases of GDM complicated by pre-eclampsia and 71% more (12 vs. 7) caseswith eventual perinatal death.

Although none of the GDM womenincluded in the above analyses receivedinsulin treatment, 12 women received in-structions for a hypocaloric or a normo-

Table 2Crude and adjusted RRs of macrosomia, preeclampsia, and perinatal death associ-ated with GDM according to ADA and WHO diagnostic criteria in the Brazilian Study of

Gestational Diabetes

Outcome

Crude Adjusted*

RR 95% CI RR 95% CI

Population

attributablefraction (%)

Macrosomia (n 3,925)ADA 1.53 0.902.49 1.29 0.732.18 0.8

WHO 1.66 1.242.20 1.45 1.061.95 4.0

Preeclampsia (n 4,572)ADA 3.62 2.056.19 2.28 1.224.16 4.8

WHO 2.43 1.573.70 1.94 1.223.03 7.9

Perinatal death (n 4,216)ADA 2.97 1.406.07 3.10 1.426.47 4.8

WHO 1.66 0.912.96 1.59 0.862.90 4.5

*Adjusted through logistic regression for center, ethnicity, age, maternal height, prepregnancy BMI, weightgain to enrollment, and also, in macrosomia analyses, for neonatal sex, and in preeclampsia and perinatal

death analyses, for parity and educational level. Odds ratios are corrected to estimate RRs (9).

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caloric diet for diabetes. The frequency ofsuch diet prescription increased with thedegree of hyperglycemia: of these 12women, 2 hada 2-h glucose level between7.8 and 8.8 mmol/l (1% of women withglucose in this range); 4 between 8.9 and10.0 mmol/l (6% of such women); and 6between 10.1 and 11.0 mmol/l (26% ofsuch women). When these diet-treatedwomen were removed from the analyses,associations of GDM with the three out-comes changed very little, with statisticalsignificance being unaltered.

CONCLUSIONS We have shownthat women diagnosed with GDM basedon a 2-h 75-g OGTT, independently ofvarious risk factors such as maternal ageand obesity, have an increased risk of de-livering a macrosomic infant, developing

preeclampsia, and suffering a perinataldeath. Based on ADA criteria, GDM pre-dicted a 30% increased risk (NS) of mac-rosomia, a 128% increased risk ofpreeclampsia, and a 210% increased riskof a perinatal death. Defined by WHO cri-teria, GDM predicted similar increasedrisks of macrosomia and preeclampsia(45 and 94%, respectively) but a notablylower increased risk of a perinatal death(59%; NS).

Our results confirm that GDM is in-dependently associated with macrosomiaand preeclampsia, as previously demon-strated by two other large cohorts of

American and Canadian women (11,12).More importantly, they show, to ourknowledge for the first time, that GDM,independent of age, obesity, and otherrisk factors, predicts perinatal mortality.

Although the background perinatal mor-tality rate in our study (24/1,000) is highcompared with the current U.S. rate,probably reflecting different socioeco-nomic settings, the even higher rateamong GDM women (39/1,000) is note-worthy.

The heterogeneity of diagnostic pro-cedures and criteria, the large variation inresearch protocols adopted across stud-ies, and the differences in obstetric careover time limit comparability of studies ofGDMpregnancy outcome associations.

Yet, a few comparisons regarding the lessstudied GDM outcome, perinatal death,deserve attention. Our results based on

ADA criteria were similar to those ofOSullivan et al. (13). We calculated fromtheir publication a crude RR of perinatalmortality for GDM of 4.2 (P 0.05) and

an adjusted RR (for age and obesity) of3.1, the latter not statistically significant(95% CI 0.7312.9). Our results based on

WHO criteria show a lower crude RR(1.66) than that of 2.84 (P 0.18, basedon a 2-h cut point of 6.7 mmol/l), calcu-lated from reported data in Pima Indians(14).

A few interpretations from our popu-lation attributable fraction data are worthconsidering. The proportion of the ad-verse pregnancy outcomes that could beattributed or associated to GDM in ourstudy was small (18%), consistent withestimates of attributable risk of macroso-mia reported by Casey et al. (15) in a largeU.S. cohort. Thus, assuming that GDMcould have been prevented or fully con-trolled, only a small proportion of the ad-ve rse out c ome s would ha ve be e n

prevented. Nonetheless, a perinatal deathis a grave outcome. The fact that as manyas 5% could be attributed to GDM, andthus perhaps prevented by clinical proto-cols for its detection and treatment, high-lights the potential clinical importance ofGDM, especially in settings in which peri-natal mortality remains a major healthproblem. This interpretation, however,assumes that successful management ofGDM will reduce perinatal mortality. Al-though macrosomia has been shown inrandomized trials to be reduced throughdetection and metabolic control of GDM,benefit in terms of perinatal mortality isfar less conclusive (16,17).

Because therisks of adverse outcomesprobably increase monotonically alongthe continuum of the hyperglycemicrange, identification of the best cut pointsfor diagnosing GDM has been problem-atic. In fact, a large international cohortstudy designed to have the power to de-fine risks associated with various rangesof hyperglycemia was recommended (18)andis currently in thefield. Thestudy willhopefully provide precise estimations of

risks associated with different ranges ofplasma glucose values obtained during a2-h 75-g OGTT. In the meantime, it isreassuring to know that the two recentofficial GDM diagnostic recommenda-tions based on a 2-h 75-g OGTT are ableto identify women with increased adversepregnancy outcomes independently ofother risk factors.

The ADA and WHO criteria eachpresent advantages and disadvantages.

ADA criteria define a more stringent (23vs. 78%) and thus logically more severe

condition. These criteria require threeblood samples, as opposed to only twowith the WHO criteria. The WHO criteriahave the simplicity of applying the samecriteria for diabetes used outside of preg-nancy. Additionally, by identifying alarger number of GDM women, these cri-teria have a greater potential for preven-tion, especially of macrosomia. However,the potential benefits to be obtainedthrough treatment of this greater numberof cases need to be weighed against theincreased use of resources required fortheir management.

Potential limitations to this studyshould be considered. Although incom-plete follow-up could produce bias, datacomparing those pregnant women ana-lyzed with those initially enrolled indi-cated only small differences, suggesting

that if bias were present, it would be mi-nor. Additionally, treatment of hypergly-cemia probably exerted little effect onGDM associations with outcomes. In part,as a result of agreement among investiga-tors on the relative lack of empirical evi-dence to support any diagnostic criteriafor GDM falling below the range of hyper-glycemia defining diabetes outside ofpregnancy, only two cases of GDM weretreated with insulin, and both were ex-cluded from these analyses. Hypocaloricdiets or diets for diabetes were used infre-quently. Reanalysis excluding these diet-treated women produced little change inthe magnitude of the associations. Finally,our study, being observational in nature,cannot estimate gains to be made throughdiagnosis and treatment of this condition.Rather, it can only highlight the potentialfor such gains.

The strengths of this study meritmention. This is one of the few large stud-ies of unselected pregnant women univer-sally evaluated with the 75-g OGTT.Because these analyses excluded womenmeeting current diagnostic criteria for di-

abetes outside of pregnancy, the magni-tude of associations here reported reflectthe risk specifically for individuals withhyperglycemia in a range where the ben-efits of diagnosis and treatment are cur-rently being debated. Of note, however,this exclusion resulted in a reduction of0.5% in the prevalence of GDM definedby each set of criteria. An additionalstrength of this study is that treatment ofhyperglycemia was minimal, and no ad-ditional exclusions were made based ongestational criteria for hyperglycemia.

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The characteristics of our study pop-ulation need to be considered while gen-e r a l i z i n g t h e s e fi n d i n g s t o o t h e rpopulations. Composed of urban womenwho sought care in public services, thestudy population did not include themore affluent segment of Brazilian soci-ety. The high perinatal mortality (24/1,000) among those studied, suggestingcausal pathways uncommon in settings oflow perinatal mortality, may limit extrap-olations to low mortality settings. On theother hand, our sample amply reflecteddifferent categories of ethnicity, age, par-ity, and nutritional status.

In conclusion,GDM detected by a 2-h75-g OGTT, as defined by ADA or WHOcriteria, was associated with the develop-ment of adverse pregnancy outcomes.Until consensual criteria are reached,

these two criteria are valid options for thedetection of a glucose tolerance state pre-dictive of adverse pregnancy outcomes.

Assuming that effective treatment is avail-able, the WHO criteria, by identifying alarger number of cases, may have greaterpotential for prevention.

Acknowledgments This study was sup-ported in part by the Brazilian Ministry ofHealth, the Pan-American Health Organiza-tion, the Foundation for the Support of Re-search of the State of Rio Grande do Sul

(FAPERGS), CNPq (the Brazilian NationalCouncil for Technologic and Scientific Devel-opment), PRONEX (Award for Groups ofExcellence), Bristol-Myers Squibb Founda-tion, Becton Dickinson, Bayer do Brasil, andBiobras.

A portion of this study was presented at the60th Annual Meeting of the American Diabe-tes Association, San Antonio, TX, 2000.

APPENDIX

The Brazilian Gestational DiabetesStudy GroupBrazilian Ministry of Health: RomeroBezerra Barbosa, Laurenice P. Lima, andEnrique Rivero Ortiz; Central Project Co-ordination: Maria Ines Schmidt, Angela J.

Reichelt, Leandro Branchtein, Maria Cris-tina Gomes Matos, Sotero Mengue, andBruce B. Duncan; Quality Control Com-mittee: Lucia Iochida, Laercio J. Franco,and Ewaldo Russo; Study Centers: Porto

Alegre : Ange la J. Re ic he lt , Le androBranchtein, Maria and Cristina GomesMatos; Salvador: Judith Maria DiasPousada, Maria Margarida dos SantosBritto, and Denise Barata; Sao Paulo:Tsuyoshi Ya ma shit a a nd C l audiaNogueira; Rio de Janeiro: Ethel R. Stam-bovsky Spichler and Claudia Martins;Manaus: Margareth Mauro Teixeira andMaria Cristina Tavares da Costa; For-taleza: Adriana Costa e Forti and EniFleck de Paula Pessoa.

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Schmidt and Associates


gestational diabetes mellitus diagnosed

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