Gestational diabetes diagnosis landmarks

A Timeline


Definition Gestational diabetes mellitus (GDM) is hyperglycemia that is first recognized at any time during pregnancy and does not reach the glycemic thresholds for diabetes2. Variable degrees of severity may be present2; 3. All women diagnosed with GDM should be evaluated postpartum, in order to detect diabetes that persists after pregnancy3. Pioneers Descriptions of pregnancy and diabetes were available long before clinical studies with a more scientific approach began. Priscilla White’s descriptions of unfavorable outcomes of diabetes in 439 pregnancies were published in the first half of the past century4. The White classification used letters of the alphabet to ascertain prognosis for both fetus and mother. As White wrote in her manuscript: "in 1948 clinical grading of the obstetric diabetic patient was made. […] Classes A to E referred to fetal risk and F to maternal risk" 4. Her classification was set based on maternal age of onset and duration of diabetes, as well as on the severity of "vascular disease". An equivalent of the metabolic alteration we now define as gestational diabetes was also described in her classification: "Class A, with highest chance for fetal survival, includes patients in whom the diagnosis of diabetes was made upon a glucose tolerance test which deviates but slightly from the normal. Such patients require no insulin and little dietary regulation" 4. This classification is no longer used5. Three other pioneers contributed to the understanding of the metabolism of the maternal/fetal/placental unit and its consequences for the fetus. In the 1960s, the Danish researcher Jorgen Pedersen formulated the Pedersen’s hypothesis which states that macrosomia is a consequence of the maternal hyperglycemic milieu leading to fetal hyperinsulinemia and subsequent excessive growth6. During the 1960s and the 1970s, Norbert Freinkel and Boyd Metzger published several studies on maternal metabolism which led to the hypothesis of "pregnancy as a tissue culture experience". The concepts of "accelerated starvation", i.e, the use of fat in metabolic routes when food is unavailable, and of "facilitated anabolism", related to "mechanisms for conserving ingested nutrients for delivery to the conceptus when the mother eats again" were described in normal pregnancies6. Moreover, since 1979, these authors have become renowned outstanding worldwide due to their effort to unify proceedings on gestational diabetes, beginning with the first workshop-conference on gestational diabetes7. Conversely, from an obstetric point of view, a study carried out by Carrington, Schurman and Reardon in the USA during the mid-1950s had already speculated on the hyperglycemia/hyperinsulinemia hypothesis8; in that paper, the authors also presented 92 cases of "prediabetic state" in pregnancy, calling those with 2-h blood glucose post-load levels over 170 mg/dl as "gestational diabetes". This was probably the first time this expression was assigned to the special type of hyperglycemia discovered in pregnancy8; 9. And in the 1960s, O’Sullivan’s studies on the diagnosis of gestational diabetes began… Present Time Although several workshop-conferences and expert meetings have been conducted to standardize GDM diagnosis, we still have multiple positions from different entities. The Table we will show next depicts current positions of some diabetes and obstetrics associations. After 2010, with the publication of the International Association of Diabetes and Pregnancy Study Group (IADPSG)10 one-step procedure, other entities endorsed the position, including the American Diabetes Association (ADA)3, the World Health Organization (WHO)2 and the Australasian Diabetes in Pregnancy Society (ADIPS)11. Nevertheless, the National Institutes of Health (NIH)12 and the American College of Obstetrics and Gynecology (ACOG)13 as well as the United States Preventive Services Task Force (USPSTF)14 did not endorse the IADPSG procedure. The Canadian Diabetes Association (CDA)15 and the National Institute for Health and Care Excellence (NICE)16 recommended their own screening and diagnostic procedures. An extensive review of other positions describing peculiar procedures in European, American and Asian countries, including China and Japan, was published by Agarwal in 201017. As the song says1: "Where do I go? Is there an answer?", we are now, and again, facing a huge dilemma on the dream toward a universal procedure for GDM diagnosis. The current IADPSG procedure raises GDM prevalence twice or more times and is also based on mathematically calculated cut points10, despite being derived from the results of a methodologically sound clinical study named "Hyperglycemia and Adverse Pregnancy Outcomes" (HAPO)18. This study evaluated more than 23 000 women and found that there was a continuous association between the risk of adverse maternal and fetal outcomes and increased plasma glucose, starting with values as low as 75 mg/dl for fasting18. Therefore, IADPSG criteria are almost as math based as those of O’Sullivan, albeit having pregnancy outcomes as endpoints18 rather than future diabetes risk, which was the endpoint adopted by O’Sullivan19. Research on GDM maternal future consequences discloses increased risk of type 2 diabetes20, whereas offspring consequences are not so well established, although obesity and type 2 diabetes risks seem to be higher9; 21; 22. For that reason, the ancient song1 is so contemporary: "Where do I go? Follow the children […]. Is there an answer in their sweet faces?". In Brazil, as well as in the USA, we still have two positions: one suggested by endocrinology societies and other recommended by obstetrics societies. Since 2014, ADA endorsed the "one-step" procedure (IADPSG) and the "two-step" procedure (NIH)3. The adoption of IADPSG criteria in Brazil raises GDM prevalence to 18%23, instead of the 7.2% figure when using WHO criteria24. Again the song is so real, when applied to GDM diagnosis: "Where will they lead me?". Raised GDM prevalence is described with the IADPSG criteria. GDM prevalence with previous criteria pointed to rates of 1.7% to 11.6% in advanced-economy countries25; and to 0.4% to 24.3%, depending on the diagnostic criteria (WHO, NDDG, ADA and others), in low and middle-income countries26. Rates of 9.3% to 25.5% were found in the HAPO centers27; despite this, lower increases were described in Irish women (from 9.4% according to WHO criteria to 12.4% according to IADPSG criteria)28. First detected hyperglycemia in pregnancy was recently estimated to be present in 16.9% of women aged 20 to 49 years old29. Strategies to implement screening were suggested with the purpose of overcoming the predicted rise in GDM prevalence with the use of IADPSG criteria30, 31. Historical landmarks that drove us to the current GDM diagnostic recommendations were plotted in the timeline we will show next. Just click on the links and you will have more information of each important event of the timeline.


400 B.C.

32 Description of the diabetic syndrome: "honeyed urine"

150 A.D.

Aretaeus of Cappadocia
(Ancient Greece)
32 diabetes (siphon) Description of the clinical aspects of diabetes: "Diabetes is a remarkable disorder […] moist and cold wasting of the flesh and limbs into urine […] patients never cease making water […] patient does not survive long when it is completely established for the marasmus produced is rapid and death is speedy"

1674 A.D.

Thomas Willis
(Oxford, England)
32 Sweet urine (tasting): diabetes mellitus

1824 A.D.

Bennewitz, H
(Berlin, Germany)
33 First case of stillbirth in "GDM"

1882 A.D.

Duncan, M.
(London, England)
33 22 cases of pregnancy and diabetes death of half mothers and babies

1909 A.D.

Williams, JW
(Johns Hopkins Hospital, USA)
33 Studies on glycosuria in pregnancy; first "GDM screening" in pregnancy

1921 A.D.

Banting & Best
32 Insulin discovery

1924 A.D.

Graham, G;
(St. Bartholomew's Hospital, Londres, UK)
33 First report of insulin treatment in pregnancy

Official positions



O'Sullivan, JB & Mahan, CM
(Boston, USA)34; 35
Cohort 1: n=752 women; mathematical criterion: mean (SD) Cohort 2: n=1 013 women, validation criterion: future diabetes
3-h 100-g OGTT (venous blood)
O’Sullivan criteria (2 cut points ≥ limits): Fasting 90 mg/dl 1-h 165 mg/dl 2-h 145 mg/dl 3-h 125 mg/dl Prevalence O’Sullivan criteria: 2.53%

WORLD HEALTH ORGANIZATION36 "Gestational diabetes refers to hyperglycaemia of diabetic levels occurring during pregnancy. This condition is responsible for embryopathia diabetica in the foetus". Cut points 2-h after 50-g or 100-g glucose load: venous glucose: ≥ 130 mg/dl capillary glucose ≥ 140 mg/dl


NATIONAL DIABETES DATA GROUP41 O'Sullivan’s criteria, plasma conversion NDDG criteria (2 cut points ≥ limits): Fasting 105 mg/dl 1-h 190 mg/dl 2-h 165 mg/dl 3-h 145 mg/dl


Adoption of the same criteria used for diabetes diagnosis in non-pregnant adults WHO criteria: Diabetes Fasting ≥ 140 mg/dl and/or 2-h ≥ 200 mg/dl IGT Fasting < 140 mg/dl + 2-h ≥ 140 mg/dl and < 200 mg/dl



Pettitt et al
n = 604 PIMA women (811 pregnancies) 2-h 75-g OGTT Diabetes: 2-h ≥ 200 mg/dl Macrosomia and mortality: raise with increasing glucose levels Increased risk of future diabetes (n = 233) 28% IGT x 8% normal

Mathematical conversion of whole blood glucose to plasma values + rounding to the nearest 5 mg/dl Carpenter & Coustan criteria (2 cut points ≥ limits): Fasting 95 mg/dl 1-h 180 mg/dl 2-h 155 mg/dl 3-h 140 mg/dl



Li & al
(Hong Kong)48
n=618 Chinese women 2-h 75-g OGTT Prevalence WHO criteria: IGT 3.9% DM 0.8%


Lind & al
(Diabetic Pregnancy Study Group - EASD)49
n = 1 009 European women 75-g OGTT (fasting, 2-h and intermediate points; venous plasma glucose or capillary whole–blood glucose) Fasting ≥ 7 mmol/l 1-h ≥ 11 mmol/l 2-h ≥ 9 mmol/l Prevalence DPSG-EASD criteria: 2-h ≥ 8 mmol/l: 7.8% 2-h ≥ 9 mmol/l: 3.2%


Martin & al
(Melbourne, Australia)50
n=1 371 Australian women Prevalence: 2-h ≥ 9 mmol/l = 1.5% 2-h ≥ 8 mmol/l = 4.2% 2-h ≥ 7.8 mmol/l = 5.2%

Sacks & al
n = 3 505 American women Universal 2-h 75-g OGTT Continuous association of weight percentiles with glucose values Mathematical criterion (mean + 2 SD, rounded to the nearest 5 mg/dl): Sacks criteria (2 cut points ≥ limits): Fasting 100 mg/dl 1-h 195 mg/dl 2-h 160 mg/dl Prevalence Sacks criteria: 3.2%

Carpenter & Coustan criteria for the 3-h 100-g OGTT


Sermer & al
(Toronto-Tri-Hospital Gestational Diabetes Project, Canada)52
n = 4 247 women screened (50-g OGTT) n = 3 836 100-g OGTT Untreated borderline GDM group (less than NDDG) had more macrosomia and cesarean delivery Prevalence NDDG criteria: 3.8%

WORLD HEALTH ORGANIZATION40 Adoption of the same criteria used for diabetes diagnosis in non-pregnant adults Gestational diabetes = GDM or impaired glucose tolerance WHO criteria: Diabetes Fasting ≥ 126 mg/dl and/or 2-h ≥ 200 mg/dl IGT Fasting < 126 mg/dl + 2-h ≥ 140 mg/dl and < 200 mg/dl


Carpenter & Coustan criteria for the 3-h 100-g OGTT


Schmidt & al
n = 4 977 Brazilian women Universal 2-h 75-g OGTT ADA: increased risk of macrosomia (NS), preeclampsia and perinatal death WHO: increased risk of macrosomia, preeclampsia and perinatal death (NS) Prevalence ADA criteria: 2.4% Prevalence WHO criteria: DM = 0.4%; IGT = 7.2%

Carpenter & Coustan criteria for the 2-h 75-g OGTT



HAPO Study18 n = 23 316 multiethnic women (9 countries) Universal 2-h 75-g OGTT "strong, continuous associations of maternal glucose levels below those diagnostic of diabetes with increased birth weight and increased cord-blood serum C-peptide levels" Prevalence IADPSG criteria: 17.8%

IADPSG10 Consensus recommendation for glucose thresholds IADPSG criteria (1 cut point ≥ limits): Fasting 92 mg/dl 1-h 180 mg/dl 2-h 153 mg/dl IADPSG criteria: "average glucose values at which odds for birth weight < 90th percentile, cord C-peptide < 90th percentile, and percent body fat < 90th percentile reached 1.75 times the estimated odds of these outcomes at mean glucose values, based on fully adjusted logistic regression models"


State of the Art

Hyperglycemia in pregnancy is initially evaluated by a fasting plasma glucose measured at the first prenatal visit: a value < 92 mg/dl is normal; ≥ 92 mg/dl and < 126 mg/dl: gestational diabetes; ≥ 126 mg/dl: diabetes 10. Eventually, an oral glucose tolerance test could be performed before the recommended 24 to 28 gestational weeks window. Glucose load and cut points adopted by several entities are in the Table. To convert mmol/l to mg/dl, multiply by 18.

Table. Gestational diabetes: current criteria for the oral glucose tolerance test (OGTT).

Position Load
Cut points
Cut points for diagnosis
Fasting 1 h 2 h 3 h
IADPSG10/ADA3 75 92
- ≥ 1
WHO2 75 92
- ≥ 1
ADIPS11 75 -
- ≥ 1
NIH12/ACOG13*; ADA3** 100 95
≥ 2
CDA15*** 75 -
- ≥ 1
NICE16 75 -
- -
- ≥ 1
USPSTF14 One-or two-step screening after 24 weeks

IADPSG: International Association of Diabetes and Pregnancy Study Group; ADA: American Diabetes Association; WHO: World Health Organization; ADIPS: Australasian Diabetes in Pregnancy Society; NIH: National Institutes of Health; ACOG: American College of Obstetrics and Gynecology; CDA: Canadian Diabetes Association; NICE: National Institute for Health and Care Excellence; USPSTF: United States Preventive Services Task Force. * 1-h 50-g oral glucose challenge test: 135 or 140 mg/dl, followed by a 3-h 100-g OGTT; two values meeting or exceeding Carpenter & Coustan criteria: fasting: 95 mg/dl; 1-h: 180 mg/dl; 2-h: 155 mg/dl; 3-h 140 mg/dl or NDDG: National Diabetes Data Group criteria: fasting 105 mg/dl; 1-h 190 mg/dl; 2-h 165 mg/dl; 3-h 145 mg/dl. ** Since 2014, ADA endorsed a "one-step" approach (IADPSG) or a "two-step" approach (NIH). *** First approach: oral glucose challenge test 1-h 50-g (140 mg/dl) followed by a 2-h 75-g OGTT: fasting 95 mg/dl, 1-h: 191 mg/dl; 2-h: 160 mg/dl; Second approach: one-step 2-h 75-g OGTT and IADPSG criteria.


"Where do I go? Is there an answer?" 1 Although an improvement towards the adoption of worldwide procedures for the diagnosis of gestational diabetes has occurred over time, we are still far from the dream expressed in John Lennon´s song Imagine 55: "You may say I'm a dreamer But I'm not the only one I hope someday you'll join us And the world will be as one"


1. Ragni G, Rado J, MacDermot G: Where Do I Go. Hair 1968 2. WHO Guidelines Approved by the Guidelines Review Committee. Diagnostic Criteria and Classification of Hyperglycaemia First Detected in Pregnancy. Geneva: World Health OrganizationCopyright (c) World Health Organization 2013.; 2013. 3. American Diabetes Association: Diagnosis and classification of diabetes mellitus. Diabetes Care 2014;37 Suppl 1:S81-90 4. White P: Pregnancy complicating diabetes. Am J Med 1949;7:609-616 5. Sacks DA, Metzger BE: Classification of diabetes in pregnancy: time to reassess the alphabet. Obstet Gynecol 2013;121:345-348 6. Freinkel N, Metzger BE: Pregnancy as a tissue culture experience: the critical implications of maternal metabolism for fetal development. Ciba Found Symp 1978:3-28 7. American Diabetes Association Workshop-Conference on gestational diabetes: summary and recommendations. Diabetes Care 1980;3:499-501 8. Carrington ER, Shuman CR, Reardon HS: Evaluation of the prediabetic state during pregnancy. Obstet Gynecol 1957;9:664-669 9. Coustan DR: Gestational diabetes mellitus. Clin Chem 2013;59:1310-1321 10. Metzger BE, Gabbe SG, Persson B, Buchanan TA, Catalano PA, Damm P, Dyer AR, Leiva A, Hod M, Kitzmiler JL, Lowe LP, McIntyre HD, Oats JJ, Omori Y, Schmidt MI: International association of diabetes and pregnancy study groups recommendations on the diagnosis and classification of hyperglycemia in pregnancy. Diabetes Care 2010;33:676-682 11. Nankervis A MH, Moses R, Ross GP, Callaway L, Porter C, Jeffries W,, Boorman C DVB, McElduff A for the Australasian Diabetes in Pregnancy, Society: ADIPS Consensus Guidelines for the Testing and Diagnosis of Gestational Diabetes Mellitus in Australia. 2013 12. National Institutes of Health consensus development conference statement: diagnosing gestational diabetes mellitus, March 4-6, 2013. Obstet Gynecol 2013;122:358-369 13. American College of Obstetricians and Gynecologists. Practice bulletin no. 137: gestational diabetes mellitus. Obstet Gynecol 2013;122:406-416 14. Moyer VA, Force USPST: Screening for gestational diabetes mellitus: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2014;160:414-420 15. Thompson D, Berger H, Feig D, Gagnon R, Kader T, Keely E, Kozak S, Ryan E, Sermer M, Vinokuroff C, Committee CDACPGE: Diabetes and pregnancy. Can J Diabetes 2013;37 Suppl 1:S168-183 16. NICE (National Institute of Care and Excellence). Diabetes in pregnancy: Management of diabetes and its complications from preconception to the postnatal period. NICE guideline 3. England: National Collaborating Centre for Women's and Children's Health; 2015. p. 681. 17. Agarwal, M: Evolution of Screening and Diagnostic Criteria for GDM Worldwide. In Gestational Diabetes During and After Pregnancy Kim CaF, A, Ed. London, Springer London, 2010 18. Metzger BE, Lowe LP, Dyer AR, Trimble ER, Chaovarindr U, Coustan DR, Hadden DR, McCance DR, Hod M, McIntyre HD, Oats JJ, Persson B, Rogers MS, Sacks DA, Group HSCR: Hyperglycemia and adverse pregnancy outcomes. N Engl J Med 2008;358:1991-2002 19. O'Sullivan JB: Diabetes mellitus after GDM. Diabetes 1991;40 Suppl 2:131-135 20. Bellamy L, Casas JP, Hingorani AD, Williams D: Type 2 diabetes mellitus after gestational diabetes: a systematic review and meta-analysis. Lancet 2009;373:1773-1779 21. Holder T, Giannini C, Santoro N, Pierpont B, Shaw M, Duran E, Caprio S, Weiss R: A low disposition index in adolescent offspring of mothers with gestational diabetes: a risk marker for the development of impaired glucose tolerance in youth. Diabetologia 2014;57:2413-20 22. Kim SY, England JL, Sharma JA, Njoroge T: Gestational diabetes mellitus and risk of childhood overweight and obesity in offspring: a systematic review. Exp Diabetes Res 2011;2011:541308 23. Trujillo J, Vigo A, Duncan BB, Falavigna M, Wendland EM, Campos MA, et al. Impact of the International Association of Diabetes and Pregnancy Study Groups criteria for gestational diabetes. Diabetes Res Clin Pract. 2015;108(2):288-95 24. Schmidt MI, Duncan BB, Reichelt AJ, Branchtein L, Matos MC, Costa e Forti A, Spichler ER, Pousada JM, Teixeira MM, Yamashita T, Group BGDS: Gestational diabetes mellitus diagnosed with a 2-h 75-g oral glucose tolerance test and adverse pregnancy outcomes. Diabetes Care 2001;24:1151-1155 25. Schneider S, Bock C, Wetzel M, Maul H, Loerbroks A: The prevalence of gestational diabetes in advanced economies. J Perinat Med 2012;40:511-520 26. Kanguru L, Bezawada N, Hussein J, Bell J: The burden of diabetes mellitus during pregnancy in low- and middle-income countries: a systematic review. Glob Health Action 2014;7:23987 27. Sacks DA, Hadden DR, Maresh M, Deerochanawong C, Dyer AR, Metzger BE, Lowe LP, Coustan DR, Hod M, Oats JJ, Persson B, Trimble ER, Group HSCR: Frequency of gestational diabetes mellitus at collaborating centers based on IADPSG consensus panel-recommended criteria: the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study. Diabetes Care 2012;35:526-528

28. O'Sullivan EP, Avalos G, O'Reilly M, Dennedy MC, Gaffney G, Dunne F, collaborators AD: Atlantic Diabetes in Pregnancy (DIP): the prevalence and outcomes of gestational diabetes mellitus using new diagnostic criteria. Diabetologia 2011;54:1670-1675 29. Guariguata L, Linnenkamp U, Beagley J, Whiting DR, Cho NH: Global estimates of the prevalence of hyperglycaemia in pregnancy. Diabetes Res Clin Pract 2014;103:176-185 30. Colagiuri S, Falavigna M, Agarwal MM, Boulvain M, Coetzee E, Hod M, Meltzer SJ, Metzger B, Omori Y, Rasa I, Schmidt MI, Seshiah V, Simmons D, Sobngwi E, Torloni MR, Yang HX: Strategies for implementing the WHO diagnostic criteria and classification of hyperglycaemia first detected in pregnancy. Diabetes Res Clin Pract 2014;103:364-372 31. Trujillo J, Vigo A, Reichelt A, Duncan BB, Schmidt MI: Fasting plasma glucose to avoid a full OGTT in the diagnosis of gestational diabetes. Diabetes Res Clin Pract 2014;105:322-326 32. Krall LP, Levine R, Barnett D: The History of Diabetes. In Joslin's Diabetes Mellitus, 13th ed. Kahn CR, Weir GC, Eds. Philadelphia, Lea & Febiger, 1994, p. 1-14 33. Hadden DR: Historical context of hyperglycemia in pregnancy. A Practical Manual of Diabetes in Pregnancy 2010:37-44 34. O'Sullivan JB, Mahan CM: Criteria for the oral glucose tolerance test in pregnancy. Diabetes 1964;13:278-285 35. O'Sullivan JB: Establishing criteria for gestational diabetes. Diabetes Care 1980;3:437-439 36. Diabetes mellitus. Report of a WHO expert committee. World Health Organ Tech Rep Ser 1965;310:1-44 37. WHO Expert Committee on Diabetes Mellitus: second report. World Health Organ Tech Rep Ser 1980;646:1-80 38. Diabetes mellitus. Report of a WHO Study Group. World Health Organ Tech Rep Ser 1985;727:1-113 39. Prevention of diabetes mellitus. Report of a WHO Study Group. World Health Organ Tech Rep Ser 1994;844:1-100 40. Definition, diagnosis and classification of diabetes mellitus and its complications : report of a WHO consultation. Part 1: Diagnosis and classification of diabetes mellitus 41. Classification and diagnosis of diabetes mellitus and other categories of glucose intolerance. National Diabetes Data Group. Diabetes 1979;28:1039-1057 42. Proceedings of the Second International Workshop-Conference on Gestational Diabetes Mellitus. October 25-27, 1984, Chicago, Illinois. Diabetes 1985;34 Suppl 2:1-130 43. Metzger BE: Summary and recommendations of the Third International Workshop-Conference on Gestational Diabetes Mellitus. Diabetes 1991;40 Suppl 2:197-201 44. 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:B161-167 45. Metzger BE, Buchanan TA, Coustan DR, de Leiva A, Dunger DB, Hadden DR, Hod M, Kitzmiller JL, Kjos SL, Oats JN, Pettitt DJ, Sacks DA, Zoupas C: Summary and recommendations of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus. Diabetes Care 2007;30 Suppl 2:S251-260 46. Pettitt DJ, Knowler WC, Baird HR, Bennett PH: Gestational diabetes: infant and maternal complications of pregnancy in relation to third-trimester glucose tolerance in the Pima Indians. Diabetes Care 1980;3:458-464 47. Carpenter MW, Coustan DR: Criteria for screening tests for gestational diabetes. Am J Obstet Gynecol 1982;144:768-773 48. Li DF, Wang ZQ, Wong VC, Ma HK: Assessment of the glucose tolerance test in unselected pregnancy using 75-g glucose load. Int J Gynaecol Obstet 1988;27:7-10 49. Lind T, Phillips PR: Influence of pregnancy on the 75-g OGTT. A prospective multicenter study. The Diabetic Pregnancy Study Group of the European Association for the Study of Diabetes. Diabetes 1991;40 Suppl 2:8-13 50. Martin FI, Ratnaike S, Wootton A, Condos P, Suter PE: The 75-g oral glucose tolerance in pregnancy. Diabetes Res Clin Pract 1995;27:147-151 51. Sacks DA, Greenspoon JS, Abu-Fadil S, Henry HM, Wolde-Tsadik G, Yao JF: Toward universal criteria for gestational diabetes: the 75-gram glucose tolerance test in pregnancy. Am J Obstet Gynecol 1995;172:607-614 52. Sermer M, Naylor CD, Farine D, Kenshole AB, Ritchie JW, Gare DJ, Cohen HR, McArthur K, Holzapfel S, Biringer A: The Toronto Tri-Hospital Gestational Diabetes Project. A preliminary review. Diabetes Care 1998;21 Suppl 2:B33-42 53. American College of Obstetricians and Gynecologists. Practice Bulletin. Clinical management guidelines for obstetrician-gynecologists. Number 30, September 2001 (replaces Technical Bulletin Number 200, December 1994). Gestational diabetes. Obstet Gynecol 2001;98:525-538 54. American Diabetes Association: Gestational Diabetes Mellitus. Diabetes Care, 2002, 25 Suppl 11:S94-S96 55. Lennon J: Imagine. Imagine 1971