Patterns of Glycemia in Normal Pregnancy
Should the current therapeutic targets be challenged?
Article Figures & Tables
Figures
- Figure 1
A: Patterns of glycemia in normal pregnancy (gestational week 33.8 ± 2.3) across 11 studies published between 1975 and 2008. One study provided useful information but required exclusion from the figure because data could not be regraphed. Methodologies used diurnal pattern characterization during inpatient admission (five studies), SMBG via reflectance photometry (one study), and CGMS (six studies) (n = 168–255; BMI range 22–28 at time of study). B: Mean pattern of glycemia across 12 studies (n = 168–255) during 33.8 ± 2.3 weeks’ gestation (weighted average ± SD, values rounded to whole numbers for clinical use). Suggested 1- and 2-h PP targets are <122 and <110 mg/dL, respectively.
Tables
- Table 1
Summary of 12 studies that met criteria for inclusion*
Author and date Purpose Research design/instruments Subjects Glucose measure/method Diet Hospital admission studies Gillmer et al. (16) To characterize diurnal glucose and insulin profiles in normal vs. pregnancies affected by diabetes Observational admission to hospital at 1000 h; hourly blood during day/every 2 h at night; 50-g 3-h OGTT 0900 h next morning n = 24 normal; n = 13 “chemical diabetes” Venous plasma glucose oxidase-peroxidase Total CHO intake 180 g; 40 g for breakfast before admission Lewis et al. (17) To characterize differences in diurnal glucose, insulin, and C-peptide in control vs. pregnant women with diabetes over 24 h Observational; 72-h hospital admission; hourly blood during day/five samples during night n = 6 normal; n = 3 “mild” diabetes; n = 4 type 1 diabetes Venous serum; rapid photoelectric 125 g CHO/day for all women Cousins et al. (18) To characterize the effect of second-/third-trimester pregnancy on glucose, insulin, and C-peptide hourly for 24 h Observational; hospital admission; hourly blood samples began after 10-h fast n = 6 nonobese “normal” women; passed OGTT Venous plasma; glucose oxidase Standard hospital meals Metzger et al. (19) To characterize the effect of gestational diabetes on diurnal profiles of glucose, lipids, and AAs in late pregnancy compared with normal pregnancy Observational; 24-h hospital admission; hourly blood during day/every 2 h at night n = 8 normal; n = 7 gestational diabetes (FBG <105); n = 6 gestational diabetes (FBG ≥105) Venous plasma; glucose oxidase Liquid meal diet: 2,110 kcal; 275 g CHO; 76 g PRO equally over three meals (0800, 1300, and 1800 h) Phelps et al. (20) To characterize diurnal profiles of glucose, insulin, FFA, TG, cholesterol, and AAs in late normal pregnancy compared with matched nonpregnant control subjects Observational; 24-h hospital admission n = 8 nonpregnant women; n = 8 “normal” pregnant women Venous plasma; glucose oxidase Liquid meal diet: 2,110 kcal; 275 g CHO; 76 g PRO equally over three meals (0800, 1300, and 1800 h) SMBG studies Parretti et al. (21) To assess diurnal glucose profiles in normal-weight women without diabetes and to assess correlations between maternal glucose and fetal growth parameters Observational; SMBG every 2 h during day/night; fixed meal times; 28, 30, 32, 34, 36, and 38 weeks’ gestation n = 51 Accutrend-α (Boehringer Mannheim, Mannheim, Germany); reflectance photometry; plasma-corrected Free-living diet CGMS studies Porter et al. (23) To compare patterns of glycemia between women with history of macrosomia or polyhydramnios vs. women without Observational/correlational; CGMS for 72 h n = 28; all without diabetes; n = 17 history of polyhydramnios or macrosomia; n = 11 no macrosomia Medtronic (Minneapolis, MN) Minimed CGMS Free-living diet Yogev et al. (22) To characterize the glycemic profile in normal-weight and obese pregnant women Observational; CGMS for 72 h n = 57; no diabetes; obese was ≥27 kg/m2 Medtronic Minimed CGMS Free-living diet Bühling et al. (25) To assess the frequency of hyperglycemia using SMBG vs. CGMS in nonpregnant, normal pregnant, and women with gestational diabetes or IGT Observational; CGMS for 72 h with SMBG 7× daily n = 8 nonpregnant; n = 56 pregnant (n = 24 no diabetes, 17 diet-controlled gestational diabetes; 17 IGT) Medtronic Minimed CGMS; Accu-Chek Sensor (Roche Diagnostics, Mannheim, Germany); SMBG: FBG, premeal, 2-h PP, hs Free-living diet for no diabetes; with diabetes: 50% CHO, 35% fat, 15% PRO as counseled Bühling et al. (24) To characterize in pregnancies affected by diabetes vs. no diabetes: 1) time of PP glucose peak; 2) PP glucose profiles; and 3) optimal time for PP glucose according to clinical outcome Observational; CGMS for 72 h n = 53; n = 36 (no diabetes); n = 17 with diabetes (13 gestational diabetes; 4 type 1 diabetes) Medtronic Minimed CGMS Free-living diet for no diabetes; with diabetes: 50% CHO, 35% fat, 15% PRO as counseled Cypryk et al. (26) To characterize blood glucose concentrations in women with gestational diabetes using CGMS Observational; CGMS for 72 h n = 19; n = 7 diet-controlled gestational diabetes; n = 5 diet + insulin-controlled gestational diabetes; n = 7 normal controls Medtronic Minimed CGMS Free-living diet Siegmund et al. (27) To characterize the glucose profile in healthy pregnant women and determine cutoff values Observational, longitudinal; CGMS for 72 h n = 32; prepregnancy BMI = 22.4 ± 2.5 kg/m2 Medtronic Minimed CGMS Free-living diet; kept diet records AA, amino acid; CHO, carbohydrate; FFA, free fatty acid; hs, bedtime; IGT, impaired glucose tolerance; PRO, protein; TG, triglyceride.
↵*Because of the complexity in study designs and space constraints, it was not possible to fully characterize all studies beyond the scope of this article.
- Table 2
Selected participant characteristics with compiled glucose variables of interest across 12 studies (weighted mean ± SD)
Study N Week of gestation BMI kg/m2 FBG 1-h Breakfast 2-h Breakfast 1-h Lunch 2-h Lunch 1-h Dinner 2-h Dinner 24-h Mean Gillmer et al. (16) 24 33.8 ± 2.2 28* 72 ± 4 99 ± 18 83 ± 16 104 ± 18 95 ± 16 84.4 ± 6.7 Lewis et al. (17) 6 40.8 ± 0.9 24.8* 80 ± 2.5 120 ± 5 105 ± 2.5 90 ± 2 105 ± 11 90 ± 2 93 ± 10 Cousins et al. (18) 6 36 ± 1 “non-obese” 74 ± 6.61 113 ± 9.8 104 ± 14 118 ± 9.8 108 ± 9.8 117 ± 12.2 105 ± 9.8 87.3 ± 4.1 Metzger et al. (19) 8 36† 89 ± 4.6% of ideal‡ 78 ± 5.66 130 ± 14.14 110 ± 19 120 ± 11.31 115 ± 19 130 ± 14.14 120 ± 17 96 ± 8.49 Phelps et al. (20) 8 36.3 ± 2.3 89 ± 4.6% of ideal‡ 78 ± 8.49 128 ± 8.49 110 ± 11 120 ± 8.49 118 ± 14 130 ± 16.97 118 ± 8 96 ± 8.49 Parretti et al. (21) 51 36 21 57.2 ± 3.9 101.2 ± 4.9 90.1 ± 4.9 101.9 ± 3.4 94.2 ± 4.1 102.2 ± 3.2 93.5 ± 5.1 77.4 ± 4.7 Porter et al. (23) 11 34.6 ± 2.6 22.8 ± 2.7‡ 77 ± 6.4 107.3 ± 13.1 107.3 ± 13.1 107.3 ± 13.1 94.1 ± 10.5 Yogev et al. (22) 42 28.9 ± 8.1 23.7 ± 1.8 72.1 ± 13 103.2 ± 13 96.8 ± 12 103.2 ± 13 96.8 ± 12 103.2 ± 13 96.8 ± 12 83.6 ± 18 Bühling et al. (25) 24 34 ± 3.7 23.0 ± 5.7‡ 97 ± 9 Bühling et al. (24) 36 32 ± 4.6 23.0 ± 5.5‡ 124.2 ± 23.4 117 ± 21.6 118.8 ± 28.8 95.4 ± 14.4 Cypryk et al. (26) 7 24–28 27.2 ± 6.3 79 ± 13§ 96 ± 11 85 ± 6 Siegmund et al. (27) 32 36 22.4 ± 2.5‡ 81.1 ± 10.8 110.6 ± 12.6 110.6 ± 12.6 110.6 ± 12.6 94 ± 9 Weighted mean, all 70.9 ± 7.8 110.8 ± 12.5 99.4 ± 9.9 107.1 ± 12.2 98.5 ± 10.4 108.9 ± 14.1 99.9 ± 10.3 88.2 ± 10.0 Weighted mean, inpatient only 75.0 ± 5.1 123.6 ± 11.2 108.7 ± 12.6 108.3 ± 13.4 97 ± 13.8 113.6 ± 15.8 102.9 ± 12.6 89.3 ± 7.3 Weighted mean, CGMS only 76.3 ± 11.4 112.2 ± 17.2 102.2 ± 12.1 109.3 ± 16.5 102.2 ± 12.1 110.0 ± 19.4 102.2 ± 12.1 91.5 ± 12.7
In this Issue
July 2011, 34(7)
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