Table 1

Clinical, demographic, and metabolic characteristics of study population (n = 392) at 3 months' and 12 months' postpartum, stratified by glucose tolerance status in pregnancy

Normal GCTAbnormal GCT
NGTNGTGIGTGDMP
n7313775107
At 3 months' postpartum
    Age (years)35.6 [32.7–39.1]34.8 [32.2–37.5]35.4 [33.3–38.5]35.2 [32.3–38.2]0.5725
    Ethnicity0.2091
        White (%)82.281.074.774.8
        Asian (%)5.59.516.08.4
        Other (%)12.39.59.316.8
    Family history of diabetes (%)39.748.549.361.70.0294
    Current smoking (%)5.53.78.03.70.5005
    Current breastfeeding (%)94.592.088.097.20.0961
    BMI (kg/m2)25.1 [22.6–28.5]25.0 [23.1–28.9]26.1 [23.3–30.1]26.7 [23.5–30.7]0.2400
    Waist circumference (cm)88.0 [80.0–95.0]85.4 [80.0–92.0]88.0 [83.0–97.0]89.4 [81.0–99.0]0.0337
    Systolic BP (mmHg)108 [101–113]108 [101–114]108 [103–115]111 [105–118]0.0539
    Diastolic BP (mmHg)66 [60–70]64 [59–70]63 [60–70]66 [60–72]0.3293
    Insulin sensitivity
        ISOGTT13.4 [9.2–17.4]12.2 [8.4–16.9]8.6 [5.9–12.9]9.0 [5.7–13.1]<0.0001
        1/HOMA-IR1.4 [1.0–1.9]1.3 [0.8–1.8]1.1 [0.6–1.6]1.0 [0.6–1.6]0.0005
    β-Cell function
        ISSI-21,123 [850–1,371]1,003 [815–1,212]868 [733–1,148]834 [628–1,062]<0.0001
        IGI/HOMA-IR13.8 [7.9–20.0]10.1 [7.0–16.2]8.4 [5.2–12.8]8.0 [4.4–13.2]<0.0001
    OGTT
        Fasting glucose (mmol/l)4.4 [4.1–4.6]4.4 [4.2–4.7]4.7 [4.3–5.0]4.7 [4.3–5.0]<0.0001
        2-h glucose (mmol/l)5.7 [4.8–6.1]5.9 [5.0–6.9]6.3 [5.2–7.3]6.7 [5.5–8.5]<0.0001
    Glucose tolerance status
        NGT (%)97.389.881.365.4<0.0001
        Isolated IFG (%)001.30.9
        Isolated IGT (%)1.410.210.728.0
        Combined IFG and IGT (%)1.401.30
        Diabetes (%)005.35.6
At 12 months' postpartum
    Current smoking (%)5.56.79.53.70.4586
    Current breastfeeding (%)95.989.888.088.80.3364
    BMI (kg/m2)24.2 [21.5–27.8]24.5 [21.9–27.9]25.0 [22.5–28.8]26.4 [22.5–30.5]0.1478
    Waist circumference (cm)82.6 [76.5–90.0]84.0 [77.2–91.0]85.5 [80.0–95.0]87.8 [80.0–96.0]0.0162
    Systolic BP (mmHg)109 [100–115]109 [102–117]110 [101–118]110 [103–119]0.4896
    Diastolic BP (mmHg)64 [59–70]65 [59–70]64 [60–70]66 [60–71]0.2260
    Insulin sensitivity
        ISOGTT12.3 [8.5–16.8]10.4 [7.1–14.9]7.7 [4.9–13.6]7.6 [4.8–11.1]<0.0001
        1/HOMA-IR1.1 [0.6–1.7]1.0 [0.6–1.6]0.9 [0.5–1.5]0.8 [0.5–1.4]0.0134
    β-Cell function
        ISSI-21,055 [866–1,433]977 [763–1,238]842 [706–1,053]787 [599–1,047]<0.0001
        IGI/HOMA-IR14.1 [9.4–22.8]10.6 [6.3–16.1]7.2 [4.3–11.8]7.2 [4.5–11.3]<0.0001
    OGTT
        Fasting glucose (mmol/l)4.5 [4.4–4.7]4.6 [4.4–5.0]4.8 [4.5–5.1]4.8 [4.5–5.2]<0.0001
        2-h glucose (mmol/l)5.4 [4.7–6.0]5.8 [5.0–7.0]6.0 [5.1–7.1]6.9 [5.6–8.3]<0.0001
    Glucose tolerance status
        NGT (%)97.388.382.767.30.0002
        Isolated IFG (%)00.71.30
        Isolated IGT (%)2.810.213.329.0
        Combined IFG and IGT (%)0000.9
        Diabetes (%)00.72.72.8
  • Continuous variables are presented as median followed by interquartile range in parentheses and categorical variables are presented as percentages. P values refer to overall differences across groups as determined by Wilcoxon rank sum test for continuous variables or χ2 test for categorical variables. BP, blood pressure.