Table 1—

Selected characteristics of case and control subjects

GDM case subjects*Control subjects
n381942
Age (years)
    <2526 (6.8)229 (24.3)
    25–2952 (13.6)226 (24.0)
    30–34132 (34.6)303 (32.2)
    ≥35171 (44.9)184 (19.5)
Race/ethnicity
    Non-Hispanic white168 (44.1)502 (53.3)
    Hispanic75 (19.7)166 (17.6)
    Asian47 (12.3)82 (8.7)
    African American29 (7.6)90 (9.6)
    Other58 (15.2)99 (10.5)
    Unknown4 (1.0)3 (0.3)
Marital status
    Never married54 (14.2)226 (24.0)
    Married300 (78.7)689 (73.1)
    Widowed, divorced, or separated16 (4.2)21 (2.2)
    Unknown11 (2.9)6 (0.6)
Education (years)
    ≤12142 (37.3)392 (41.6)
    13–15124 (32.5)267 (28.3)
    1673 (19.2)159 (16.9)
    ≥1737 (9.7)115 (12.2)
    Unknown5 (1.3)9 (1.0)
Parity
    0148 (38.8)405 (43.0)
    1125 (32.8)343 (36.4)
    ≥2108 (28.3)194 (20.6)
Family history of diabetes
    First-degree relative87 (22.8)104 (11.0)
    Second-degree relative98 (25.7)204 (21.7)
    None154 (40.4)561 (59.6)
    Unknown42 (11.0)73 (7.7)
Family history of hypertension
    First-degree relative113 (29.7)233 (24.7)
    Second-degree relative41 (10.8)100 (10.6)
    None168 (44.1)532 (56.5)
    Unknown59 (15.5)77 (8.2)
BMI at first prenatal visit (kg/m2)
    <2014 (3.7)98 (10.4)
    20.1–24.996 (25.2)423 (44.9)
    25.0–29.9126 (33.1)250 (26.5)
    ≥30142 (37.3)149.0 (15.8)
    Unknown3 (0.8)22.0 (2.3)
Blood pressure during pregnancy
    Normal197 (51.7)668 (70.9)
    Prehypertenison147 (38.6)240 (25.5)
    Hypertension37 (9.7)34 (3.6)
  • Data are n (%).

  • *

    * GDM equals NDDG criteria. Normal BP: ≤120/80 mmHg; prehypertension: 120–139/80–89 mmHg; and hypertension: ≥140 and/or ≥90 mmHg or use of antihypertensive drugs.