Table 3 Stratified effect estimates of the association between pregnancy loss and rheumatoid arthritis risk

Rural

1.14 (1.06–1.23)*

1.12 (1.02–1.22)*

1.13 (1.01–1.26)*

1.23 (1.09–1.40)*

1.07 (1.03–1.11)*

Urban

1.11 (1.03–1.19)*

1.08 (0.99–1.16)

1.12 (1.03–1.22)*

1.17 (1.06–1.29)*

1.05 (1.02–1.09)*

< 5000

1.10 (0.96–1.27)

1.07 (0.91–1.26)

1.01 (0.82–1.25)

1.29 (1.04–1.61)*

1.06 (1.00–1.14)

5000–19,999

1.10 (1.02–1.19)*

1.06 (0.97–1.15)

1.15 (1.04–1.26)*

1.15 (1.03–1.28)*

1.05 (1.02–1.09)*

≥20,000

1.15 (1.06–1.26)*

1.14 (1.03–1.25)*

1.13 (1.02–1.26)*

1.21 (1.07–1.37)*

1.06 (1.02–1.10)*

< 16.8

1.10 (1.03–1.18)*

1.06 (0.98–1.14)

1.12 (1.03–1.22)*

1.17 (1.07–1.29)*

1.06 (1.02–1.09)*

≥16.8

1.15 (1.06–1.25)*

1.14 (1.04–1.25)*

1.13 (1.01–1.26)*

1.20 (1.06–1.37)*

1.06 (1.02–1.10)*

< 25

1.15 (1.08–1.23)*

1.13 (1.04–1.22)*

1.14 (1.05–1.25)*

1.23 (1.11–1.36)*

1.07 (1.04–1.10)*

≥25

1.08 (1.00–1.17)

1.04 (0.95–1.15)

1.11 (1.00–1.23)

1.14 (1.01–1.28)*

1.05 (1.01–1.09)*

Smoker

0.90 (0.74–1.08)

0.82 (0.66–1.03)

0.90 (0.70–1.16)

1.05 (0.81–1.36)

1.01 (0.93–1.10)

Non-smoker

1.14 (1.08–1.20)*

1.11 (1.05–1.18)*

1.14 (1.07–1.23)*

1.19 (1.10–1.29)*

1.06 (1.03–1.09)*

Alcohol drinker

1.09 (1.00–1.19)

1.06 (0.96–1.18)

1.09 (0.98–1.22)

1.14 (1.01–1.29)*

1.04 (1.00–1.08)*

Non-alcohol drinker

1.13 (1.06–1.21)*

1.10 (1.02–1.19)*

1.14 (1.04–1.24)*

1.21 (1.10–1.34)*

1.06 (1.03–1.10)*