Table 2.
Demographic characteristics of pregnancies in the final study sample (n=2,540 pregnancies, 4,551 samples)
| Preeclampsia Cases (N = 1,545) | Controls (N = 995) | |||
|---|---|---|---|---|
| Maternal Age (mean(SD), years) | 29.3 (4.9) | 30.1 (4.4) | ||
| No. | % | No. | % | |
| Maternal Education | ||||
| < High School | 132 | 8.5 | 73 | 7.3 |
| High School Graduate | 439 | 28.4 | 264 | 26.5 |
| University Degree | 831 | 53.8 | 574 | 57.7 |
| Missing | 143 | 9.3 | 84 | 8.4 |
| Body Mass Index (kg/m2) | ||||
| Underweight (<18.5) | 25 | 1.6 | 32 | 3.2 |
| Normal weight (18.5–24.9) | 712 | 46.1 | 629 | 63.2 |
| Overweight (25.0–29.9) | 444 | 28.7 | 186 | 18.7 |
| Obese (30.0+) | 264 | 17.1 | 95 | 9.6 |
| Missing | 100 | 6.5 | 53 | 5.3 |
| Maternal Smoking | ||||
| Smoking in weeks 11–20 | 120 | 7.8 | 95 | 9.6 |
| Missing | 83 | 5.4 | 44 | 4.4 |
| Smoking in third trimester | 71 | 4.6 | 64 | 6.4 |
| Missing | 159 | 10.3 | 86 | 8.6 |
| Nulliparous | 1012 | 65.5 | 407 | 40.9 |
| Preterm (< 37 weeks) | 332 | 21.5 | 33 | 3.3 |
| Small for gestational age (SGA) (< 10th percentile)a | 349 | 22.6 | 77 | 7.7 |
| Preeclampsia subtypes | ||||
| Severe | 308 | 19.9 | ||
| Onset <34 weeks | 277 | 17.9 | ||
| Delivery <34 weeks | 132 | 8.5 | ||
| Accompanied by SGAa | 349 | 22.6 | ||
a
Population percentiles derived from Norwegian distribution, eSnurra Norway