Table 2.
The odds ratio of spontaneous abortion associated different socioeconomic status
| Women without SA n = 76,034 | Women with SA n = 5,418 | Crude OR (95% CI) | Adjusted OR (95% CI) a | |
|---|---|---|---|---|
| Region (%) | ||||
| Urban | 45.64 | 24.73 | 1.00 | 1.00 |
| Rural | 54.36 | 75.27 | 2.56 (2.40–2.72) | 1.68 (1.54–1.84) |
| p for difference b | <0.001 | <0.001 | ||
| Annual household income, Yuan (%) | ||||
| < 20,000 | 52.68 | 64.89 | 1.00 | 1.00 |
| ≥ 20,000 | 47.32 | 35.11 | 0.60 (0.57–0.64) | 0.90 (0.84–0.97) |
| p for trendc | <0.001 | 0.003 | ||
| Highest level of education (%) | ||||
| Primary school and below | 30.05 | 37.49 | 1.00 | 1.00 |
| Middle school | 40.72 | 43.13 | 0.85 (0.80–0.90) | 0.98 (0.92–1.04) |
| High school and above | 29.23 | 19.38 | 0.53 (0.49–0.57) | 0.90 (0.82–0.98) |
| p for trend c | <0.001 | 0.033 | ||
| Current occupation (%) | ||||
| Agricultural worker and related workers | 39.17 | 59.06 | 1.00 | 1.00 |
| Factory worker | 25.95 | 14.29 | 0.37 (0.34–0.40) | 0.59 (0.53–0.66) |
| Professional worker | 16.79 | 9.93 | 0.39 (0.36–0.43) | 0.75 (0.66–0.84) |
| Housewife | 6.26 | 7.95 | 0.84 (0.76–0.94) | 1.11 (0.99–1.24) |
| Unemployed | 5.11 | 3.14 | 0.41 (0.35–0.48) | 0.84 (0.71–1.01) |
| Other or not stated | 6.72 | 5.63 | 0.56 (0.49–0.63) | 0.95 (0.83–1.09) |
| p for heterogeneity d | <0.001 | 0.008 | ||
NB The COR and AOR in the text represent the crude OR and adjusted OR in the table, respectively
a Adjustments: rural/urban, income, education, occupation, tea consumption, alcohol consumption, smoking status, induced abortion count
b p for difference was used to test the difference between rural and urban area as binary variable
c p for trend was used to test the significance of trend on ordinal categorical variables like income and educational level
d p for heterogeneity was used to test the heterogeneity between occupation as unordered categorical variables
Bold values signify significant findings p <0.05