Table 1.
Descriptive statistics for the HAPO North American cohort
| All (N = 6,159) | No GDM (n = 5,020) | GDM based on IADPSG criteria (n = 878) | GDM based on CC criteria (n = 261) | P value* | |
|---|---|---|---|---|---|
| Maternal characteristics | |||||
| Age at OGTT, years | 30.3 (5.7) | 30.1 (5.8) | 31.0 (5.6) | 32.3 (5.3) | <0.001 |
| BMI at OGTT, kg/m2 | 28.8 (5.4) | 28.2 (4.9) | 31.5 (6.4) | 31.6 (5.8) | <0.001 |
| Height at OGTT, cm | 162.5 (6.8) | 162.7 (6.8) | 161.9 (6.7) | 160.9 (6.7) | <0.001 |
| Mean arterial pressure at OGTT, mmHg | 83.2 (8.0) | 82.7 (7.9) | 85.4 (8.5) | 86.0 (8.3) | <0.001 |
| Prepregnancy BMI, kg/m2 | 25.0 (5.3) | 24.4 (4.9) | 27.5 (6.4) | 27.7 (5.9) | <0.001 |
| Fasting plasma glucose, mg/dL | 82.6 (6.9) | 80.6 (5.2) | 90.8 (6.3) | 93.0 (7.8) | — |
| 1-h plasma glucose, mg/dL | 133.0 (30.7) | 125.1 (22.8) | 160.0 (28.1) | 195.3 (15.2) | — |
| 2-h plasma glucose, mg/dL | 110.1 (23.3) | 104.8 (18.8) | 125.9 (22.6) | 159.0 (23.4) | — |
| Field center, n (%) | <0.001 | ||||
| Bellflower, CA | 1,903 (30.9) | 1,468 (29.2) | 340 (38.7) | 95 (36.4) | |
| Chicago, IL | 738 (12.0) | 616 (12.3) | 97 (11.1) | 25 (9.6) | |
| Cleveland, OH | 784 (12.7) | 598 (11.9) | 142 (16.2) | 44 (16.9) | |
| Providence, RI | 746 (12.1) | 640 (12.8) | 82 (9.3) | 24 (9.2) | |
| Toronto, ON, Canada | 1,988 (32.2) | 1,698 (33.8) | 217 (24.7) | 73 (28.0) | |
| Race/ethnicity, n (%) | <0.001 | ||||
| White | 3,099 (50.3) | 2,620 (52.2) | 371 (42.3) | 108 (41.4) | |
| Black | 525 (8.5) | 438 (8.7) | 67 (7.6) | 20 (7.7) | |
| Hispanic | 1,984 (32.2) | 1,547 (30.8) | 343 (39.1) | 94 (36.0) | |
| Asian | 397 (6.5) | 290 (5.8) | 76 (8.7) | 31 (11.9) | |
| Other | 154 (2.5) | 125 (2.5) | 21 (2.4) | 8 (3.1) | |
| Parity, n (%) | <0.001 | ||||
| 0 | 2,939 (47.7) | 2,465 (49.1) | 359 (40.9) | 115 (44.1) | |
| 1 | 1,949 (31.6) | 1,587 (31.6) | 288 (32.8) | 74 (28.4) | |
| ≥2 | 1,271 (20.6) | 968 (19.3) | 231 (26.3) | 72 (27.6) | |
| Alcohol use during pregnancy (any), n (%) | 203 (3.3) | 172 (3.4) | 24 (2.7) | 7 (2.7) | 0.49 |
| Smoking during pregnancy (any), n (%) | 301 (4.9) | 226 (4.5) | 56 (6.4) | 19 (7.3) | 0.011 |
| Family history of diabetes, n (%) | 1,386 (22.5) | 1,031 (20.5) | 261 (29.7) | 94 36.0) | <0.001 |
| Family history of hypertension, n (%) | 2,650 (43.0) | 2,134 (42.5) | 389 (44.3) | 127 (48.7) | 0.11 |
| Hospitalization before delivery, n (%) | 240 (3.9) | 179 (3.6) | 48 (5.5) | 13 (5.0) | 0.018 |
| Maternal UTI, n (%) | 729 (11.8) | 575 (11.5) | 125 (14.2) | 29 (11.1) | 0.058 |
| Newborn characteristics | |||||
| Birth weight, g | 3,408 (516) | 3,386 (505) | 3,505 (539) | 3,510 (599) | — |
| Body fat, % | 12.3 (3.5) | 12.1 (3.5) | 13.2 (3.7) | 13.3 (3.8) | — |
| Sum of skin folds, mm | 12.3 (2.6) | 12.1 (2.5) | 13.1 (2.8) | 13.4 (3.1) | — |
| Cord blood C-peptide, ug/L | 0.98 (0.57) | 0.93 (0.53) | 1.17 (0.84) | 1.36 (0.78) | — |
| Cord blood glucose, mg/dL | 76.9 (15.9) | 76.4 (15.4) | 78.3 (16.8) | 80.7 (20.0) | <0.001 |
| Gestational age, weeks | |||||
| At OGTT | 27.6 (1.7) | 27.6 (1.7) | 27.5 (1.8) | 27.7 (1.7) | 0.30 |
| At delivery | 39.6 (1.3) | 39.6 (1.2) | 39.5 (1.3) | 39.2 (1.3) | — |
| Sex, n (%) | 0.84 | ||||
| Male | 3,191 (51.8) | 2,593 (51.7) | 463 (52.7) | 135 (51.7) | |
| Female | 2,968 (48.2) | 2,427 (48.3) | 415 (47.3) | 126 (48.3) |
Data are mean (SD), unless otherwise stated. *Characteristics were compared across the categories of no GDM, GDM diagnosed based on IADPSG criteria, and GDM based on CC criteria (also GDM based on IADPSG criteria) using ANOVA for continuous variables and χ2 tests for categorical variables. Maternal glucose values were not compared across groups because they were used to define the IADPSG and CC categories. Newborn birth weight, body fat, sum of skinfolds, cord blood C-peptide, and gestational age at delivery were not compared across groups because these variables were dichotomized and treated as formal outcomes in adjusted logistic regression analyses. UTI, urinary tract infection.