IADPSG criteria for diagnosing gestational diabetes mellitus and predicting adverse pregnancy outcomes

Transcription

1 Journal of Perinatology (2014) 34, & 2014 Nature America, Inc. All rights reserved /14 ORIGINAL ARTICLE IADPSG criteria for diagnosing gestational diabetes mellitus and predicting adverse pregnancy outcomes OBJECTIVE: To evaluate the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria versus the American Diabetes Association (ADA) criteria for diagnosing gestational diabetes mellitus (GDM) in China. STUDY DESIGN: Overall, 3083 women with a singleton pregnancy underwent a 75-g, 2-h oral glucose tolerance test between 24 and 28 weeks of pregnancy, and both IADPSG and ADA criteria were used for GDM diagnosis. Adverse pregnancy outcomes (APOs), including preterm birth, required Cesarean section, preeclampsia, macrosomia and low birth weight, were recorded and analyzed. RESULT: IADPSG and ADA criteria diagnosed 19.9% and 7.98% of women with GDM, respectively (Po0.001). IADPSG criteria has a stronger capacity of predicting APOs than ADA criteria (odds ratio (OR) ¼ 1.84, 95% confidence interval (CI): for IADPSG, and OR ¼ 1.54, 95% CI: for ADA). CONCLUSION: IADPSG criteria increase GDM diagnosis by almost twofold. GDM diagnosed by IADPSG criteria is more associated with APOs, although the economic impact needs further evaluation. Journal of Perinatology (2014) 34, ; doi: /jp ; published online 14 November 2013 Keywords: GDM; diagnosis; glucose tolerance test; maternal and neonatal outcomes INTRODUCTION Gestational diabetes mellitus (GDM) is one of the most common medical complications during pregnancy and its prevalence appears to be increasing around the world, probably because of the increase in the number of women of child-bearing age who are overweight, of older age, and have sedentary lifestyles. 1 Recent randomized controlled trials 2 and a blinded observational study 3 have confirmed the association between maternal hyperglycemia and adverse pregnancy outcomes. There is mounting evidence that treatment of even mild GDM reduces morbidity for both the mother and baby. 4 Therefore, clinical diagnosis of GDM, antepartum fetal surveillance and according interventions are important to reduce perinatal morbidity and mortality associated with GDM. However, the diagnostic criteria for GDM vary greatly worldwide among different countries or even different regions in the same country, although great effort has been invested to reach a consensus over the past half century. 5 9 Some diagnostic criteria are based on that used in non-pregnant women, whereas others 10 that are based on data from pregnant women are simply defined mathematically (as being two s.d. above the mean), rather than on data derived from the adverse pregnancy outcomes. 11 To improve the quality of perinatal medicine, GDM values in the prediction of adverse pregnancy outcome have been extensively assessed over the decades. 12,13 Currently, the criteria recommended by the American Diabetes Association (ADA) and aimed to reduce adverse pregnancy outcomes have generally been used worldwide as a gold standard. In 2002, the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study 3 reported that the increase in glucose levels close to but lower than that traditionally required for the diagnosis of GDM were significantly associated with subsequent adverse pregnancy outcomes. Mainly based on the HAPO study, the International Association of Diabetes and Pregnancy Study Groups (IADPSG) recommended new GDM diagnostic criteria in ,14 Since the recommendation, the IADPSG criteria have been evaluated or validated worldwide, but with controversies and inconsistencies. 8,15 17 Whereas most studies 9,16 have demonstrated a good association between GDM diagnosed based on the criteria and adverse pregnancy outcomes, others 15 have failed to show such an association. Moreover, these criteria have rarely been validated in an Asian population, 16 especially in Chinese, who account for one-fifth of the world population. Therefore, the aim of this prospective study was to evaluate the IADPSG criteria, in parallel to the ADA criteria, and to determine association between GDM and adverse pregnancy outcomes in Chinese pregnant women. MATERIALS AND METHODS Study subjects Pregnant women who had their initial prenatal visit before 24 gestational weeks at the Antenatal Clinic of Beijing Friendship Hospital, Capital Medical University, and were to receive prenatal care and to deliver at the institution between January 2012 and March 2013 were consecutively enrolled for the study. We excluded women with abortion before 28 weeks gestation, those with multiple gestations confirmed by ultrasonography, those with a history of pre-gestational diabetes mellitus and those without a documented GDM screening test result. In addition, pregnant women who were diagnosed with overt or pre-gestational diabetes mellitus at the initial prenatal visit were also excluded. The demographic and clinical characteristic such as maternal age, height, weight, pre-pregnancy body mass index, parity, primary indications of Cesarean section such as breech presentation and previous Cesarean section, previous GDM history and complications such as induction of labor Department of Obstetrics and Gynecology, Beijing Friendship Hospital, Capital Medical University, Beijing, China. Correspondence: Dr L Lin, Department of Obstetrics and Gynecology, Beijing Friendship Hospital, Capital Medical University, 95 Yongan Road, Xicheng District, Beijing , China. linli488@163.com Received 29 July 2013; revised 21 September 2013; accepted 7 October 2013; published online 14 November 2013

2 and premature rupture of membranes were recorded or calculated in a pre-designed case record form. The study was approved by the Institutional Ethics Committee of Beijing Friendship Hospital and written informed consent was obtained from each participant. Screening, diagnosis and treatment of GDM At the initial prenatal visit, the fasting plasma glucose was estimated for all women. As recommended by the IADPSG criteria, 75-g oral glucose tolerance test (OGTT) was also performed at this visit for pregnant women at higher risk, that is, those who were older than 25 years, obese (body mass index430 or greater kg m 2 ), with a family history (first or second degree-relatives) of diabetes mellitus, or a history of previous GDM or a macrosomic infant. 18 The women who were found to have diabetes mellitus, using standard criteria (a fasting glucose level of 126 mg dl 1 (7.0 mmol l 1 ) or higher, 2-h glucose level of 200 mg dl (mmol l 1 ) or higher, a random plasma glucose level 4200 mg dl 1 (11.1 mmol l 1 ) plus classical signs and symptoms of hyperglycemia), were diagnosed with overt diabetes mellitus, not GDM. 13 Women with overt diabetes were excluded from this study. Women with fasting plasma glucose X92 mg dl 1 (X5.1 mmol l 1 ) but 126 mg dl 1 (o7.0 mmol l 1 ) at the initial visit were diagnosed with GDM, 14 and included in the study. Then, at the week visit, all women, except for those who were excluded, received universal screening for GDM by means of a 75-g, 2-h OGTT. The standard protocols were used for the test. Briefly, after a 72-h no carbohydrate restriction and a 10-h overnight fast, 3 ml of venous plasma samples were collected for the measurement of fasting, 1 and 2 h plasma glucose levels. The plasma glucose levels were estimated by the glucose oxidase method (Beckman Coulter Instruments, Indianapolis, IN, USA), and GDM was diagnosed according to the IADPSG and ADA criteria, respectively. Table 1 shows a comparison of the IADPSG and ADA diagnostic criteria. 19 The management of GDM was consistent with the standard clinical practice, which consisted of dietary control and proper exercise, with targets of fasting glucose level of 95 mg dl 1 (o5.3 mmol l 1 ) and 2-h postprandial glucose level of 120 mg dl 1 (o6.7 mmol l 1 ). If these goals were still not attained, insulin therapy was added according to the guidelines of Committee on Technical Bulletins of the American College of Obstetricians and Gynecologists. 20 Adverse pregnancy outcomes During the follow-up visits, clinical data and adverse pregnancy outcomes were recorded and compared among different groups. In the present study, we included the adverse pregnancy outcomes that have been shown to be improved with the treatment of GDM in randomized controlled trials or to be significantly associated with GDM in retrospective studies. 4,21 Namely, these adverse pregnancy outcomes were preterm delivery (that is, delivery before 37 gestational weeks), requirement for Cesarean section, preeclampsia (a disorder of widespread vascular endothelial malfunction and vasospasm that occurs after 20 weeks gestation and can present as late as 4 6 weeks postpartum including mild preeclampsia, severe preeclampsia and eclampsia), neonatal Table 1. The IADPSG and the ADA criteria for diagnosis of gestational diabetes mellitus hypoglycemia, macrosomia (defined as birth weightx4000 g) and low birth weight (LBW, defined as birth weightp2500 g). Statistical analysis Categorical variables were reported as percentages or frequencies (%) and continuous variables were reported using mean (±s.d.). Pearson s w 2 -test, or Fisher s exact test, was used to compare the difference in categorical variables between or among different groups; the odds ratios (OR) and 95% confidence intervals (CIs) were also calculated. The independent sample t-test was used to compare the difference in the continuous variables between groups. McNemar s test was used to compare the prevalence of GDM diagnosed between the two criteria. All statistical analyses were performed using SPSS software package (SPSS, Chicago, IL, USA) version A P-value of o0.05 was taken to signify statistical significance. RESULTS Prevalence of GDM diagnosed by IADPSG and ADA criteria Overall, 3629 pregnant women were enrolled for eligibility at the initial visit. Of them, 546 were excluded due to overt or pregestational diabetes mellitus (n ¼ 79), abortion before 28 gestational weeks (n ¼ 305), multiple pregnancy (n ¼ 45) and without a documented GDM screening test result (n ¼ 117). Thus, a total of 3083 women were recruited in the study and underwent a diagnostic 75-g/2-h OGTT at their gestational weeks visits, including 67 women who were diagnosed with GDM at the initial visit based on the IADPSG criteria (Figure 1). Of the 3083 women, 612 (19.9%) and 246 (7.98%) cases were diagnosed with GDM, based on IADPSG and the ADA diagnostic criteria, respectively (Po0.001). By definition, all women diagnosed with GDM by the ADA criteria were also diagnosed with GDM by the IADPSG criteria. The 67 women who were diagnosed with GDM at the initial visit by the IADPSG criteria also met the ADA criteria for GDM. Fasting glucose concentrations during the 75-g/2-h OGTT at weeks was abnormal in 384 (62.7%) of the 612 women and in 153 (62.2%) of the 246 women with GDM, according to the IADPSG and ADA criteria, respectively (P ¼ 0.880). Accordingly, 2471 and 2837 cases were considered as healthy pregnant women with normal glucose tolerance, based on the IADPSG and ADA criteria, respectively (Figure 1). All women received prenatal care according to the standard clinical practice and delivered in our hospital. Maternal characteristics according to the IADPSG and ADA criteria are shown in Table 2. Associations between GDM diagnosed by the IADPSG or ADA criteria and adverse pregnancy outcomes Overall, the pre-defined adverse pregnancy outcomes occurred in 1929 (62.6%) of the women, and diagnosis of GDM by the IADPSG 101 Test IADPSG criteria (any one of the cut-off values below) ADA criteria (at least two of the cut-off values below) a,b Screening 3629 Fasting glucose 1-h glucose 2-h glucose X92 X180 X153 X95 X180 X155 Abbreviations: ADA, American Diabetes Association; IADPSG, International Association of Diabetes and Pregnancy Study Groups. a The ADA has recently endorsed the IADPSG criteria. 19 b 75-g OGTT was used in this study, so ADA criteria here referred to criteria for 75-g OGTT. By ADA criteria 3083 enrolled 546 excluded By IADPSG criteria 246 GDM 2837 normal 612 GDM 2471 normal Figure 1. The recruitment procedures and results of the study. ADA, the American Diabetes Association; GDM, gestational diabetes mellitus, IADPSG, International Association of Diabetes and Pregnancy Study Groups. & 2014 Nature America, Inc. Journal of Perinatology (2014),

3 102 was associated with a significantly increased number (n ¼ 449) of women with adverse pregnancy outcomes, compared with that (n ¼ 174) for the ADA criteria (Table 3). According to the IADPSG criteria, women with GDM showed significantly higher percentages of overall adverse pregnancy outcomes than those without GDM (73.4% vs 59.9%, OR ¼ 1.84, 95% CI ¼ , w 2 ¼ , Po0.001). Specifically, women with GDM had significantly higher percentages of fetal macrosomia (13.1% vs 7.9%, OR ¼ 1.77, 95% CI ¼ , w 2 ¼ , Po0.001), higher percentage of requirement for Cesarean section (54.9% vs 49.0%, OR ¼ 1.27, 95% CI ¼ , w 2 ¼ 6.815, P ¼ 0.009) and lower percentage of LBW (3.8% vs 7.0%, OR ¼ 0.52, 95% CI ¼ , w 2 ¼ 8.841, P ¼ 0.003), and preterm delivery (6.2% vs 9.0%, OR ¼ 0.67, 95% CI ¼ , w 2 ¼ 5.018, P ¼ 0.025), compared with those without GDM (Table 3). According to the ADA criteria, women with GDM appeared to have a higher percentage of overall adverse pregnancy outcomes than those without GDM (70.7% vs 61.1%, OR ¼ 1.54, 95% CI ¼ , w 2 ¼ 8.935, P ¼ 0.003). Specifically, women with GDM showed significantly higher percentages of fetal macrosomia (12.6% vs 8.6%, OR ¼ 1.54, 95% CI ¼ , w 2 ¼ 4.554, P ¼ 0.033) compared with those without GDM (Table 3). DISCUSSION In the present study, an incidence rate of GDM of 19.9% was detected by the IADPSG criteria, whereas the rate was 7.98% for the ADA criteria, indicating that the IADPSG criteria increased the diagnostic yield for GDM by B12%, or by nearly twofold, compared with the ADA criteria. The incidence of GDM differs depending on the populations being screened and the diagnostic criteria being used. It has been estimated that, if the IADPSG criteria were applied to the HAPO cohort (that is, Caucasian population in the USA), the incidence of GDM (including overt diabetes) would be increased from 3 5 to 17.8%. 14,22 A recent study by Agarwal et al. 23 from the United Arab Emirates comparing IADPSG with ADA criteria also found a threefold (37.7% vs 12.9%) increase with the newer criteria. It was noticed that the rates were higher in our study and the study by Agarwal et al. 23, which was also consistent with the observation that GDM Table 2. Maternal characteristics in women with or without gestational diabetes mellitus (GDM) according to the IADPSG and ADA criteria Characteristics IADPSG criteria ADA criteria GDM (N ¼ 612) Non-GDM (N ¼ 2471) GDM (N ¼ 246) Non-GDM (N ¼ 2837) Average age (years) 30.1± ± ± ±3.6 Gestational age (mean±s.d.) 39.64± ± ± ±1.55 Parity (n) 1.07± ± ± ±0.30 Primigravida (n (%)) 567 (92.6) 2245 (90.9) 224 (91.1) 2588 (91.2) Second pregnancy (n (%)) 43 (7.0) 207 (8.4) 22 (8.9) 228 (8.0) Third pregnancy (n (%)) 2 (0.3) 18 (0.7) 0 (0) 20 (0.7)) Fourth pregnancy (n (%)) 0 (0) 1 (0.0) 0 (0) 1 (0.0) Pre-gestational diabetes mellitus (n (%)) 4 (8.9) 16 (7.1) 1 (0.4) 20 (0.7) Pre-gestational BMI 22.3± ± ± ±2.9 Induction of labor (n (%)) 119 (19.4) 497 (20.1) 53 (21.5) 563 (19.8) Prior Cesarean section (n (%)) 21 (3.4) 76 (3.1) 9 (3.7) 88 (3.1) Breech presentation (n (%)) 19 (3.1) 55 (2.2) 6 (2.4) 68 (2.4) Treated with insulin (n (%)) 72 (11.4) a 0 (0) 37 (15.0) b 0 (0) Preterm premature rupture of membranes (n (%)) 122 (19.9) 490 (19.8) 48 (19.4) 564 (19.9) Abbreviations: ADA, American Diabetes Association; BMI, body mass index;gdm, gestational diabetes mellitus; IADPSG, International Association of Diabetes and Pregnancy Study Groups. a Significant for GDM by IADPSG vs control groups (n ¼ 2471); b Significant for GDM by ADA vs control group (n ¼ 2837). Table 3. Association of GDM diagnosed with IADPSG and ADA criteria and adverse pregnancy outcomes Adverse pregnancy outcomes IADPSG criteria ADA criteria GDM (N ¼ 612) Non-GDM (N ¼ 2471) OR (95% CI) GDM (N ¼ 246) Non-GDM (N ¼ 2837) OR (95% CI) Macrosomia (n (%)) 80 (13.1) a 194 (7.9) 1.77 ( ) 31 (12.6) b 243 (8.6) 1.54 ( ) Cesarean section (n (%)) 336 (54.9) a 1211 (49.0) 1.27 ( ) 136 (55.3) 1411 (49.7) 1.25 ( ) Preeclampsia (n (%)) 44 (7.2) 140 (5.7) 1.29 ( ) 17 (6.9) 167 (5.9) 1.19 ( )) Low body weight (n (%)) 23 (3.8) a 174 (7.0) 0.52 ( ) 11 (4.5) 186 (6.6) 0.67 ( ) Preterm delivery (n (%)) 38 (6.2) a 223 (9.0) 0.67 ( ) 16 (6.5) 245 (8.6) 0.74 ( ) Need for intravenous glucose 7 (1.1) 28 (1.1) 1.01 ( ) 3 (1.2) 32 (1.1) 1.08 ( ) treatment (n (%)) Total 449 (73.4) a 1480 (59.9) 1.84 ( ) 174 (70.7) 1755 (61.1) 1.54 ( ) Abbreviations: ADA, American Diabetes Association; CI, confidence interval; GDM, gestational diabetes mellitus; IADPSG, International Association of Diabetes and Pregnancy Study Groups; OR, odds ratio. a Significant for GDM by IADPSG vs control groups (n ¼ 2471). b Significant for GDM by ADA vs control group (n ¼ 2837). Journal of Perinatology (2014), & 2014 Nature America, Inc.

4 occurs more frequently in Asian women than Caucasian women. 24 Furthermore, universal screening by 75-g OGTT was used in the present study, which, on one hand, will detect more women with GDM and thus might prevent or reduce the incidence of adverse pregnancy events, but on the other hand, will result in a substantial number of women receiving the 75-g OGTT test, and thus impose an increasing financial burden, compared with the ADA criteria. Pregnancy outcome is the key to determine the suitability of diagnostic criteria for GDM. In the present study, GDM diagnosed by the IADPSG criteria was associated with a significantly increased number of women with adverse maternal and neonatal outcomes, compared with that diagnosed by the ADA criteria, and the IADPSG criteria has a stronger capacity of predicting adverse pregnancy outcomes than the ADA criteria (84.0% versus 54.0%). GDM is a well-established risk factor for fetal macrosomia, 25 which has been associated with an increased risk for obstetric problems and birth injury, adult obesity and glucose intolerance in late adolescence and young adulthood. 26 In the present study, the incidence of macrosomia for women with GDM diagnosed by the IADPSG and the ADA criteria was increased by 77.0% and 54.0%, respectively, compared with non-gdm. There were more cases of macrosomia in the women with GDM than in those with normal glucose tolerance. These findings also suggest that GDM is associated with macrosomia in the offspring even after glucose control. This finding also suggests that even a mildly impaired glucose tolerance is associated with macrosomia in the offspring, and this group of pregnant women should receive close monitoring to reduce the potential adverse effects. Interestingly, there were fewer cases of LBW in the women with GDM diagnosed by IADPSG criteria or ADA criteria. A possible explanation for this finding is that the moderate plasma glucose level is reasonable for fetal growth and that mild hyperglycemia may be beneficial for some fetuses with growth restriction to gain normal weight. This notion can be indirectly supported by the finding on the positive association between GDM and macrosomia observed in the present study. This phenomenon also reminds us that diet control should be controlled in an adequate extent and that lowering the target of controlled plasma glucose levels might be associated with LBW. An unexpected result was that the incidence of preterm delivery was not elevated in GDM women, by both the IADPSG and ADA criteria. While the increased risk of macrosomia is wellrecognized in association with GDM, the 33.0% decrease in the risk of preterm delivery in women with GDM diagnosed by the IADPSG criteria observed in the present study was contrary to that in the HAPO study, which showed an association between increasing maternal glucose levels and prematurity. 3 There are multiple causes for preterm delivery including premature rupture of membranes, placenta previa, intrauterine infection and cervical incompetence that threaten the safety of the mother or the fetus. In women with overt diabetes mellitus and/or GDM and whose hyperglycemia is not well controlled, the incidence of preterm delivery might be elevated mainly because of complications with early onset of severe preeclampsia or premature rupture of membranes. However, in the present study, women with overt diabetes mellitus were excluded, and all women were carefully monitored and glucose levels were well controlled. The incidence of preeclampsia and premature rupture of membranes were similar between GDM and non-gdm according to both the ADA criteria and the IADPSG criteria. Therefore, GDM was no longer predictive of preterm delivery. Other adverse outcomes such as preeclampsia and neonatal hypoglycemia were similar between GDM and the non-gdm group by both sets of criteria. A possible explanation for this finding is that more attention and management provided to women diagnosed with GDM may have successfully reduced the risk of preeclampsia and neonatal hypoglycemia. The diagnostic thresholds chosen in the IADPSG criteria are arbitrary and will continue to miss a proportion of cases with abnormal glucose metabolism, and thus leave open the possibility of adverse pregnancy outcomes due to untreated GDM. 14 Therefore, further studies are necessary to ascertain the consequences and/or effects of the new criteria on the incidence and outcomes of GDM. This is the first study that evaluates the new IADPSG criteria to diagnose GDM and predict maternal and fetal outcomes in China. We confirmed that IADPSG criteria identified a group of women who would be classified as normal, but develop pregnancy outcomes resembling those in women diagnosed with GDM by the ADA criteria. Therefore, the IADPSG criteria appears to be superior to the ADA criteria in the following aspects. First, the IADPSG criteria could identify more women with subsequent adverse pregnancy outcomes (84.0% vs 54.0%). Second, it is required that, in the IADPSG criteria, high-risk women be tested for overt diabetes mellitus and GDM at their initial prenatal visit, and those diagnosed with overt diabetes mellitus or GDM 13 would receive a closer monitoring from early pregnancy. Third, universal screening at weeks gestation recommended in the IADPSG criteria is more sensitive than selective screening generally adapted in the ADA criteria and more practical when a family history of diabetes mellitus cannot be reliably obtained. 27 Finally, according to the IADPSG criteria, abnormality in the plasma glucose level (that is, above the cut-off values) at any one of the three time points in the OGTT is enough to make a diagnosis of GDM. Based on this point, Agarwal et al. 28 reported that the initial fasting plasma glucose result can help decide if the pregnant woman should continue with her OGTT, to relieve the economic burden of universal screening. Indeed, in the present study, fasting glucose concentrations during the 75-g/2-h OGTT at weeks was abnormal in 384 (62.7%) women, indicating that almost two-thirds of women can be diagnosed with GDM by the fasting glucose levels without further OGTT. There are a few concerns with application of the IADPSG criteria. The first one is over-diagnosis of GDM. However, this is not the case due to the stronger association between the adverse pregnancy outcomes with GDM as diagnosed by the IADPSG criteria, compared with the ADA criteria. The second concern is the costs. Compared with the ADA criteria that have been widely used as a gold standard, the IADPSG criteria use lower cut-off values for glucose levels at fasting and 2 h and require abnormality only at single time point, which would impose a potential economic impact. Therefore, further randomized clinical trials are needed to determine the short- and long-term cost-effectiveness, optimal treatment targets and strategies in terms of plasma glucose levels. 29 In addition, there is a room to modify the criteria as described above, to reduce the costs. In conclusion, application of the IADPSG criteria increases the diagnoses of GDM in pregnant women by almost twofold in China, compared with the ADA criteria. GDM diagnosed by the IADPSG criteria appears to be more associated with adverse pregnancy outcomes. Therefore, the IADPSG criteria are suitable in China but the economic impact needs to be further evaluated. CONFLICT OF INTEREST The authors declare no conflict of interest. ACKNOWLEDGEMENTS This work was supported by a grant from Capital Medical University (Grant No# 12JL- L02). We thank all the colleagues who took care of the pregnant women included in our study, and Medjaden Bioscience Limited for assisting in the preparation of this manuscript. 103 & 2014 Nature America, Inc. Journal of Perinatology (2014),

5 104 REFERENCES 1 Getahun D, Nath C, Ananth CV, Chavez MR, Smulian JC. Gestational diabetes in the United States: temporal trends 1989 through Am J Obstet Gynecol 2008; 198(5): 525.e Crowther CA, Hiller JE, Moss JR, McPhee AJ, Jeffries WS, Robinson JS et al. Effect of treatment of gestational diabetes mellitus on pregnancy outcomes. New Engl J Med 2005; 352(24): Metzger BE, Lowe LP, Dyer AR, Trimble ER, Chaovarindr U, Coustan DR et al. Hyperglycemia and adverse pregnancy outcomes. New Engl J Med 2008; 358(19): Landon MB, Spong CY, Thom E, Carpenter MW, Ramin SM, Casey B et al. A multicenter, randomized trial of treatment for mild gestational diabetes. NEnglJ Med 2009; 361(14): Blank A, Grave GD, Metzger BE. Effects of gestational diabetes on perinatal morbidity reassessed. Report of the International Workshop on Adverse Perinatal Outcomes of Gestational Diabetes Mellitus, December 3-4, Diabetes Care 1995; 18(1): Coustan DR, Lowe LP, Metzger BE. The hyperglycemia and adverse pregnancy outcome (HAPO) study: can we use the results as a basis for change? J Matern Fetal Neonatal Med 2010; 23(3): Carpenter MW, Coustan DR. Criteria for screening tests for gestational diabetes. Am J Obstet Gynecol 1982; 144(7): O Sullivan EP, Avalos G, O Reilly M, Dennedy MC, Gaffney G, Dunne F et al. Atlantic Diabetes in Pregnancy (DIP): the prevalence and outcomes of gestational diabetes mellitus using new diagnostic criteria. Diabetologia 2011; 54(7): Lapolla A, Dalfrà MG, Ragazzi E, De Cata AP, Fedele D. New International Association of the Diabetes and Pregnancy Study Groups (IADPSG) recommendations for diagnosing gestational diabetes compared with former criteria: a retrospective study on pregnancy outcome. Diabet Med 2011; 28(9): WHO. Expert Committee on Diabetes Mellitus: second report. World Health Organ Tech Rep Ser 1980; 646: Coustan DR, Lowe LP, Metzger BE, Dyer AR. Groups IAoDaPS. The Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study: paving the way for new diagnostic criteria for gestational diabetes mellitus. Am J Obstet Gynecol 2010; 202(6654): e651 e Metzger BE, Coustan DR. Summary and recommendations of the Fourth International Workshop-Conference on Gestational Diabetes Mellitus. The Organizing Committee. Diabetes Care 1998; 21(Suppl 2): B161 B American Diabetes Association. Gestational diabetes mellitus. Diabetes Care 2004; 27(Suppl 1): S88 S Metzger BE, Gabbe SG, Persson B, Buchanan TA, Catalano PA, Damm P et al. International association of diabetes and pregnancy study groups recommendations on the diagnosis and classification of hyperglycemia in pregnancy. Diabetes Care 2010; 33(3): Reyes-Muñoz E, Parra A, Castillo-Mora A, Ortega-González C. Effect of the diagnostic criteria of the International Association of Diabetes and Pregnancy Study Groups on the prevalence of gestational diabetes mellitus in urban Mexican women: a cross-sectional study. Endocr Pract 2012; 18(2): Morikawa M, Yamada T, Akaishi R, Nishida R, Cho K, Minakami H. Change in the number of patients after the adoption of IADPSG criteria for hyperglycemia during pregnancy in Japanese women. Diabetes Res Clin Pract 2010; 90(3): Wendland EM, Torloni MR, Falavigna M, Trujillo J, Dode MA, Campos MA et al. Gestational diabetes and pregnancy outcomes--a systematic review of the World Health Organization (WHO) and the International Association of Diabetes in Pregnancy Study Groups (IADPSG) diagnostic criteria. BMC Pregnancy Childbirth 2012; 12: Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Diabetes Care 1997; 20(7): American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care 2010; 33(Suppl 1): S62 S ACOG technical bulletin. Diabetes and pregnancy. Number 200--December 1994 (replaces No. 92, May 1986). Committee on Technical Bulletins of the American College of Obstetricians and Gynecologists. Int J Gynaecol Obstet 1995; 48(3): Cheng YW, Block-Kurbisch I, Caughey AB. Carpenter-Coustan criteria compared with the national diabetes data group thresholds for gestational diabetes mellitus. Obstet Gynecol 2009; 114(2 Pt 1): Metzger BE. Summary and recommendations of the Third International Workshop-Conference on Gestational Diabetes Mellitus. Diabetes 1991; 40(Suppl 2): Agarwal MM, Dhatt GS, Shah SM. Gestational diabetes mellitus: simplifying the international association of diabetes and pregnancy diagnostic algorithm using fasting plasma glucose. Diabetes Care 2010; 33(9): Ferrara A, Hedderson MM, Quesenberry CP, Selby JV. Prevalence of gestational diabetes mellitus detected by the national diabetes data group or the carpenter and coustan plasma glucose thresholds. Diabetes Care 2002; 25(9): Galerneau F, Inzucchi SE. Diabetes mellitus in pregnancy. Obstet Gynecol Clin North Am 2004; 31(4): , xi xii. 26 Dabelea D, Hanson RL, Lindsay RS, Pettitt DJ, Imperatore G, Gabir MM et al. Intrauterine exposure to diabetes conveys risks for type 2 diabetes and obesity: a study of discordant sibships. Diabetes 2000; 49(12): Karcaaltincaba D, Kandemir O, Yalvac S, Güvendag-Guven S, Haberal A. Prevalence of gestational diabetes mellitus and gestational impaired glucose tolerance in pregnant women evaluated by National Diabetes Data Group and Carpenter and Coustan criteria. Int J Gynaecol Obstet 2009; 106(3): Agarwal MM, Dhatt GS, Punnose J. Gestational diabetes: utility of fasting plasma glucose as a screening test depends on the diagnostic criteria. Diabet Med 2006; 23(12): Leary J, Pettitt DJ, Jovanovic L. Gestational diabetes guidelines in a HAPO world. Best Pract Res Clin Endocrinol Metab 2010; 24(4): Journal of Perinatology (2014), & 2014 Nature America, Inc.