Table 1.
Characteristics of Chinese women of childbearing age in the study
| Characteristic | South | North | Total | ||||||
|---|---|---|---|---|---|---|---|---|---|
| East | West | East | West | ||||||
| Urban | Rural | Urban | Rural | Urban | Rural | Urban | Rural | ||
| Number of women | 100 | 100 | 100 | 100 | 201 | 202 | 100 | 100 | 1003 |
| Age (years, mean ± SD) | 25.1 ± 3.3 | 25.0 ± 3.2 | 23.2 ± 2.9 | 26.4 ± 2.6 | 26.0 ± 3.4 | 26.9 ± 2.9 | 25.3 ± 3.0 | 26.3 ± 3.5 | 25.7 ± 3.3 |
| BMI (mean ± SD) | 19.9 ± 2.4 | 21.4 ± 3.5 | 20.1 ± 2.3 | 21.3 ± 2.4 | 21.2 ± 2.4 | 22.9 ± 3.0 | 21.0 ± 2.6 | 20.9 ± 2.3 | 21.3 ± 2.8 |
| Han ethnic group (%) | 100.0 | 100.0 | 97.0 | 95.0 | 95.5 | 95.5 | 99.0 | 100.0 | 97.3 |
| Level of education (%) | |||||||||
| Elementary | 1.0 | 3.0 | 0.0 | 11.0 | 0.0 | 6.9 | 1.0 | 6.0 | 3.6 |
| Middle School | 6.0 | 66.0 | 11.1 | 79.0 | 2.0 | 73.8 | 4.0 | 48.0 | 36.7 |
| High School | 41.0 | 28.0 | 10.1 | 9.0 | 47.0 | 18.3 | 38.0 | 28.0 | 28.5 |
| College and above | 52.0 | 3.0 | 78.8 | 1.0 | 51.0 | 1.0 | 57.0 | 18.0 | 31.3 |
| Current cigarette smoking (%) | 2.0 | 0.0 | 3.0 | 2.0 | 1.0 | 5.4 | 1.0 | 1.0 | 2.2 |
| Current alcohol drinking (%) | 4.0 | 2.0 | 3.0 | 4.0 | 4.5 | 1.5 | 4.0 | 0.0 | 2.9 |
| Oral contraception use (%) | 3.0 | 0.0 | 1.0 | 0.0 | 1.5 | 2.5 | 0.0 | 0.0 | 1.2 |
| Multivitamin and/or folic acid use (%) | 6.0 | 1.0 | 8.0 | 0.0 | 3.0 | 0.5 | 4.0 | 4.0 | 3.0 |