Table 1.
The pre-pregnancy and pregnancy characteristics of participants stratified by the number of pregnancies
| Singleton (n = 357,877) |
Multiple gestations (n = 4,944) |
P-value | |
|---|---|---|---|
| Age (years) | 29.95 ± 3.27 | 30.02 ± 3.38 | < 0.01 |
| Advanced maternal age (%) | 30,899 (8.63) | 685 (13.86) | < 0.01 |
| Primiparity (%) | 214,451 (59.92) | 3,893 (78.74) | < 0.01 |
| Preeclampsia (%) | 5919 (1.65) | 374 (7.56) | < 0.01 |
| Atrial fibrillation (%) | 176 (0.05) | 3 (0.06) | 0.72 |
| Regular exercise (%) | 27,520 (7.69) | 420 (8.50) | 0.04 |
| Smoker (%) | 9,859 (2.75) | 108 (2.18) | 0.01 |
| BMI (kg/m2) | 20.75 ± 5.81 | 20.85 ± 2.71 | 0.23 |
| Obesity (%) | 23,335 (6.52) | 371 (7.50) | < 0.01 |
| Systolic BP (mmHg) | 110.4 ± 10.54 | 110.6 ± 10.77 | 0.08 |
| Diastolic BP (mmHg) | 69.52 ± 7.86 | 69.60 ± 7.94 | 0.50 |
| Fasting glucose (mg/dL) | 85.93 ± 14.42 | 86.34 ± 12.87 | 0.04 |
| DM (%) | 3,324 (0.93) | 71 (1.44) | < 0.01 |
| TC (mg/dL) | 174.0 ± 34.56 | 175.1 ± 35.20 | 0.03 |
| High TC (%) | 63,302 (17.69) | 923 (18.67) | 0.07 |
| AST (mg/dL) | 19.53 ± 11.38 | 19.89 ± 10.70 | 0.03 |
| ALT (mg/dL) | 15.41 ± 15.48 | 15.81 ± 14.27 | 0.07 |
| Abnormal LFT (%) | 13,531 (3.78) | 205 (4.15) | 0.18 |
Regular exercise was defined as moderate-intensity exercise performed at least 3 d/wk
Obesity by BMI; BMI ≥ 25 kg/m2, DM; fasting glucose ≥ 126 mg/dL at the NHSE or a medical claim for DM as a primary or secondary diagnosis before pregnancy based on ICD-10 codes, high TC; TC ≥ 200 mg/Dl, abnormal LFT; AST ≥ 31 or ALT ≥ 31 mg/dL
Values are expressed as mean (SD) or n(%)
BMI body mass index, BP blood pressure, DM diabetes mellitus, TC total cholesterol, AST aspartate aminotransferase, ALT alanine aminotransferase, LFT liver function test