Table 2. Characteristics of matched cases and controls.
| Characteristic | Cases | Controls | p value |
| Number (N) | 140 | 270 | N/A |
| rs2794521, C allele freq | 41/201* = 16.9% | 92/254 = 26.6% | 0.008** |
| rs3091244, T allele freq | 87/169 = 34.0% | 101/281 = 26.4% | 0.050 |
| rs3093068, G allele freq | 20/246 = 8.1% | 16/366 = 4.4% | 0.078 |
| rs876538, T allele freq | 40/280 = 14.3% | 119/440 = 27% | 0.010 |
| Age, mean years (SD) | 23.88 (6.4) | 23.74 (5.40) | 0.768*** |
| Parity (N,% nulliparous) | 94/140 (67.1%) | 114/270 (42.2%) | <0.001**** |
| Weight at first prenatal | 181.7 (46.82) | 161.6 (41.35) | <0.001*** |
| Body-Mass index (BMI) | 30.92 (7.39) | 27.42 (6.88) | <0.001*** |
| Gestational diabetes, N (% yes) | 15/122 (12.3%) | 9/199 (4.8%) | 0.031**** |
| Weeks of gestation at delivery | 36.67 (3.96) | 39.52 (1.82) | <0.001*** |
| Birth weight of infant, grams | 3013 (967) | 3431 (623) | <0.001*** |
| Mother's educational attainment (years of education) | 11.95 (1.85) | 12.15 (2.44) | 0.405*** |
| Maternal smoking, N (% yes) | 38/95 (40.0%) | 76/160 (47.5%) | 0.543**** |
| Maternal smoking (Mean cigarettes smoked) | 6.75 (18.03) | 10.51 (23.20) | 0.047*** |
| Mean systolic blood pressure | 163.8 (18.3) | 132.9 (12.9) | <0.001*** |
| Mean diastolic blood pressure | 97.6 (10.1) | 78.6 (8.4) | <0.001*** |
*41/201 indicates 41 minor alleles (T in this case) and 201 major alleles for a total of 242.
**Differences in allele frequency evaluated with Chi square test.
***Differences between means evaluated with paired t test.
****Differences between discrete variables evaluated with McNemar's Chi square test.