Table 1

Summary of 12 studies that met criteria for inclusion*

Author and datePurposeResearch design/instrumentsSubjectsGlucose measure/methodDiet
Hospital admission studies
Gillmer et al. (16)To characterize diurnal glucose and insulin profiles in normal vs. pregnancies affected by diabetesObservational admission to hospital at 1000 h; hourly blood during day/every 2 h at night; 50-g 3-h OGTT 0900 h next morningn = 24 normal; n = 13 “chemical diabetes”Venous plasma glucose oxidase-peroxidaseTotal 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 hObservational; 72-h hospital admission; hourly blood during day/five samples during nightn = 6 normal; n = 3 “mild” diabetes; n = 4 type 1 diabetesVenous serum; rapid photoelectric125 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 hObservational; hospital admission; hourly blood samples began after 10-h fastn = 6 nonobese “normal” women; passed OGTTVenous plasma; glucose oxidaseStandard 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 pregnancyObservational; 24-h hospital admission; hourly blood during day/every 2 h at nightn = 8 normal; n = 7 gestational diabetes (FBG <105); n = 6 gestational diabetes (FBG ≥105)Venous plasma; glucose oxidaseLiquid 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 subjectsObservational; 24-h hospital admissionn = 8 nonpregnant women; n = 8 “normal” pregnant womenVenous plasma; glucose oxidaseLiquid 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 parametersObservational; SMBG every 2 h during day/night; fixed meal times; 28, 30, 32, 34, 36, and 38 weeks’ gestationn = 51Accutrend-α (Boehringer Mannheim, Mannheim, Germany); reflectance photometry; plasma-correctedFree-living diet
CGMS studies
Porter et al. (23)To compare patterns of glycemia between women with history of macrosomia or polyhydramnios vs. women withoutObservational/correlational; CGMS for 72 hn = 28; all without diabetes; n = 17 history of polyhydramnios or macrosomia; n = 11 no macrosomiaMedtronic (Minneapolis, MN) Minimed CGMSFree-living diet
Yogev et al. (22)To characterize the glycemic profile in normal-weight and obese pregnant womenObservational; CGMS for 72 hn = 57; no diabetes; obese was ≥27 kg/m2Medtronic Minimed CGMSFree-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 IGTObservational; CGMS for 72 h with SMBG 7× dailyn = 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, hsFree-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 outcomeObservational; CGMS for 72 hn = 53; n = 36 (no diabetes); n = 17 with diabetes (13 gestational diabetes; 4 type 1 diabetes)Medtronic Minimed CGMSFree-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 CGMSObservational; CGMS for 72 hn = 19; n = 7 diet-controlled gestational diabetes; n = 5 diet + insulin-controlled gestational diabetes; n = 7 normal controlsMedtronic Minimed CGMSFree-living diet
Siegmund et al. (27)To characterize the glucose profile in healthy pregnant women and determine cutoff valuesObservational, longitudinal; CGMS for 72 hn = 32; prepregnancy BMI = 22.4 ± 2.5 kg/m2Medtronic Minimed CGMSFree-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.