The Relationship between a High Carbohydrate Diet and Oral Glucose Tolerance Test in Pregnancy

Abstract

Objective The aim of this study is to examine the impact of carbohydrate ratios in the diet consumed one day prior to the 75-g oral glucose screening test on both the screening test values and the diagnosis of gestational diabetes mellitus in the unselective pregnant population.

Material-Method 83 pregnant women who were under observation in the antenatal clinic of our hospital and underwent glucose tolerance tests were included in the study. The patients were given training by a dietitian to keep nutrition records of the day prior to glucose loading during their previous visits before any glucose loading. A carbohydrate intake of 40–60% was considered as the normal range in terms of the percentage of carbohydrates in the diet. A carbohydrate percentage above 60% was considered to be a high carbohydrate intake. The carbohydrate percentages in their diet over the past 24 hours was compared with the effect on the glucose tolerance test.

Results Out of the 83 pregnant women included in the study, 40 of them had a high carbohydrate diet (HCD) prior to the oral glucose tolerance test (OGTT), and the average carbohydrate percentage of this diet was found to be 62%. The remaining 43 patients had an average carbohydrate percentage of 49% and belonged to the group that had a normal carbohydrate diet (NCD). Out of the 83 pregnant women, 33 of them were at high risk for gestational diabetes mellitus (GDM). In the high-risk patient group, 16 patients had an NCD intake, while 17 patients had a HCD intake. It was determined that a high carbohydrate diet had no significant effect on fasting, first-hour, and second-hour glucose levels, as well as the diagnosis of gestational diabetes mellitus (GDM), in both the unselective population and the high-risk patient population.

Conclusion In our study, we concluded that the high carbohydrate ratios in the diets of pregnant women one day prior did not affect the OGTT results or the GDM ratios. This indicates that there is no need for a preparatory diet prior to the OGTT in women with normal dietary habits.

Key words

pregnancy - gestational diabetes - high carbohydrate diet - glucose tolerance test

Publication History

Received: 09 June 2023

Accepted after revision: 19 July 2023

Article published online:
17 August 2023

• References

• 1 Venkatesh KK, Lynch CD, Powe CE. et al. Risk of adverse pregnancy outcomes among pregnant individuals with gestational diabetes by race and ethnicity in the United States, 2014–2020. JAMA 2022; 327: 1356-1367
• 2 Ye W, Luo C, Huang J. et al. Gestational diabetes mellitus and adverse pregnancy outcomes: systematic review and meta-analysis. BMJ 2022; 377: e067946
• 3 ElSayed NA, Aleppo G, Aroda VR. et al. 2. Classification and Diagnosis of Diabetes: Standards of Care in Diabetes–2023. Diabetes Care 2023; 46: S19-S40
• 4 ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus. Obstet Gynecol 2018; 131: e49-e64
• 5 McLaren RA, Ruymann KR, Ramos GA. et al. Early screening for gestational diabetes mellitus: a meta-analysis of randomized controlled trials. Am J Obstet Gynecol MFM 2022; 4: 100737
• 6 Metzger BE, Buchanan TA, Coustan DR. et al. Summary and recommendations of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus. Diabetes Care 2007; 30: 251-260
• 7 American Diabetes Association. 2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes–2020. Diabetes Care 2020; 43: 14-31
• 8 Conn JW. Interpretation of glucose tolerance test: necessity of standard preparatory diet. Am J Med Sci 1940; 199: 555-564
• 9 Crowe SM, Mastrobattista JM, Monga M. Oral glucose tolerance test and the preparatory diet. Am J Obstet Gynecol 2000; 182: 1052-1054
• 10 Rosenberg EA, Seely EW, James K. et al. Relationship between carbohydrate intake and oral glucose tolerance test results among pregnant women. Diabetes Res Clin Pract 2021; 176: 108869
• 11 Buhling KJ, Elsner E, Wolf C. et al. No influence of high- and low-carbohydrate diet on the oral glucose tolerance test in pregnancy. Clin Biochem 2004; 37: 323-327
• 12 Entrekin K, Work B, Owen J. Does a high carbohydrate preparatory diet affect the 3-hour oral glucose tolerance test in pregnancy?. J Matern Fetal Med 1998; 7: 68-71
• 13 International Association of Diabetes and Pregnancy Study Groups Consensus Panel. Metzger BE, Gabbe SG. et al. International association of diabetes and pregnancy study groups recommendations on the diagnosis and classification of hyperglycemia in pregnancy. Diabetes Care 2010; 33: 676-682
• 14 Türkiye Endokrinoloji ve Metabolizma Derneği Diabetes Mellitus ve Komplikasyonlarının Tanı, Tedavi ve İzlem Kılavuzu 2022. Available online at: https://file.temd.org.tr/Uploads/publications/guides/documents/diabetesmellitus_2022 (Accessed May 15, 2023)
• 15 Sweeting A, Mijatovic J, Brinkworth GD. et al. The carbohydrate threshold in pregnancy and gestational diabetes: How low can we go?. Nutrients 2021; 13: 2599
• 16 https://hsgm.saglik.gov.tr/depo/birimler/saglikli-beslenme-hareketli-hayat db/Turkiye Beslenme_Rehberi_ TUBER_18_04_2019.Pdf (Accessed May 10, 2023)
• 17 Carpenter MW, Coustan DR. Criteria for screening tests for gestational diabetes. Am J Obstet Gynecol 1982; 144: 768-773
• 18 Bilous RW, Jacklin PB, Maresh MJ. et al. Resolving the gestational diabetes diagnosis conundrum: the need for a randomized controlled trial of treatment. Diabetes Care 2021; 44: 858-864
• 19 American Diabetes Association. Standards of medical care in diabetes–2011. Diabetes Care 2011; 34: 11-61
• 20 Bogdanet D, O’Shea P, Lyons C. et al. The oral glucose tolerance test–Is ıt time for a change? – A literature review with an emphasis on pregnancy. J Clin Med 2020; 9: 3451
• 21 Takizawa M, Kaneko T, Kohno K. et al. The relationship between carbohydrate intake and glucose tolerance in pregnant women. Acta Obstet Gynecol Scand 2003; 82: 1080-1085
• 22 Institute of Medicine. Otten JJ, Hellwig JP, Meyers LD. Dietary reference intakes: The essential guide to nutrient requirements. Washington, DC: The National Academies Press; 2006
• 23 Hernandez TL, Van Pelt RE, Anderson MA. et al. A higher-complex carbohydrate diet in gestational diabetes mellitus achieves glucose targets and lowers postprandial lipids: a randomized crossover study. Diabetes Care 2014; 37: 1254-1262