Table 1.
Prepregnancy demographics for women giving birth in Maine, 2000–2010.
| Variable | N | Grand mean | 95% CI | P trend | Slope | |
|---|---|---|---|---|---|---|
| Maternal age (yrs) | 12561 | 28.1 | 28.0 | 28.3 | 0.351 | |
| Maternal age 1st birth (yrs) | 6124 | 26.1 | 26.0 | 26.3 | 0.804 | |
| Maternal BMI | 12561 | 25.8 | 25.6 | 25.9 | <0.0001 | 0.153 |
| No previous live birth (%) | 12460 | 45.7 | 44.7 | 46.8 | 0.042 | 0.014 |
| Married (%) | 12561 | 63.6 | 62.5 | 64.6 | <0.0001 | −0.062 |
| Maternal education ≤12 yrs (%) | 12514 | 45.2 | 44.2 | 46.2 | 0.0009 | −0.023 |
| Household income <$20 k/yr (%) | 11981 | 31.8 | 30.8 | 32.8 | 0.210 | |
| Maternal race not white (%) | 12270 | 3.1 | 2.7 | 3.5 | 0.020 | 0.049 |