Table 1.
Maternal characteristics of the placental abruption cases and controls
| Characteristics | Study groups | P-valueb | |||
|---|---|---|---|---|---|
| Placental abruption (N = 103) | Comparison group (N = 102) | ||||
| n | % | n | % | ||
| Maternal age at delivery (years)a | 27.0 ± 6.6 | 26.8 ± 5.8 | 0.89 | ||
| Maternal age at delivery (years) | |||||
| <20 | 18 | 17.5 | 10 | 9.8 | 0.29 |
| 20–34 | 71 | 68.9 | 78 | 76.5 | |
| ≥35 | 14 | 13.6 | 14 | 13.7 | |
| Gravidity | |||||
| 1 | 45 | 43.7 | 37 | 36.3 | 0.21 |
| 2–3 | 40 | 38.8 | 52 | 51.0 | |
| ≥4 | 18 | 17.5 | 13 | 12.7 | |
| Nulliparous | 46 | 44.7 | 37 | 36.3 | 0.22 |
| Maternal education ≤ high school | 76 | 73.8 | 69 | 67.7 | 0.29 |
| Single marital status | 19 | 18.5 | 14 | 13.7 | 0.29 |
| Employed during pregnancy | 58 | 56.3 | 44 | 43.1 | 0.06 |
| Received prenatal care | 94 | 91.3 | 97 | 95.1 | 0.41 |
| Did not take prenatal vitamins | 11 | 10.7 | 14 | 13.7 | 0.53 |
| Smoked during pregnancy | 3 | 2.9 | 1 | 1.0 | 0.62 |
| Alcohol consumption during pregnancy | 9 | 8.7 | 0 | 0.0 | 0.003 |
| Drug abuse during pregnancy | 1 | 1.0 | 0 | 0.0 | – |
| Chronic hypertension | 3 | 2.9 | 1 | 1.0 | 0.42 |
| Preeclampsia | 11 | 10.7 | 4 | 3.9 | 0.11 |
| Pre-pregnancy body mass index (kg/m2)a | 23.5 ± 3.2 | 23.6 ± 3.5 | 0.84 | ||
| Lean (<18.5) | 4 | 3.9 | 1 | 1.0 | 0.57 |
| Normal (18.5–24.9) | 75 | 72.8 | 74 | 72.5 | |
| Overweight (25–29.9) | 18 | 17.5 | 21 | 20.6 | |
| Obese (≥30.0) | 6 | 5.8 | 6 | 5.9 | |
| Gestational age at delivery | 34.7 ± 4.3 | 39.1 ± 1.4 | <0.001 | ||
| Infant birthweight (g) | 2388 ± 921 | 2835 ± 939 | <0.001 | ||
| Stillbirth | 21 | 20.4 | 0 | 0.0 | <0.001 |
aMean ± standard deviation (SD)
bP-value from Student’s t test for continuous variables and Chi square test/Fisher’s Exact test for categorical variables