From: Risk factors for ectopic pregnancy: a multi-center case-control study
 | EP | IUP | OR [95 % CI] | p value | ||
---|---|---|---|---|---|---|
n a | (%) | n a | (%) | |||
Age (year) | ||||||
 ≤20 | 24 | (1.00) | 32 | (1.33) | Reference | 0.16 |
 20–24 | 363 | (15.06) | 398 | (16.47) | 1.22 [0.70, 2.10] | |
 25–29 | 753 | (31.23) | 772 | (31.95) | 1.30 [0.76, 2.23] | |
 30–34 | 793 | (32.89) | 755 | (31.25) | 1.40 [0.82, 2.40] | |
 35–39 | 332 | (13.77) | 322 | (13.33) | 1.38 [0.79, 2.39] | |
 ≥40 | 146 | (6.06) | 137 | (5.67) | 1.42 [0.80, 2.53] | |
Marital status | ||||||
 Married | 2067 | (85.80) | 2088 | (86.42) | Reference | 0.56 |
 Unmarried | 342 | (14.20) | 328 | (13.58) | 0.92 [0.78, 1.08] | |
Birth place | Â | Â | Â | Â | Â | Â |
 Shanghai | 698 | (28.95) | 775 | (32.08) | Reference | <10−3 |
 Outside of Shanghai | 1713 | (71.05) | 1641 | (67.92) | 1.16 [1.03, 1.31] | |
Education attainment | ||||||
 Collage or above | 1061 | (44.01) | 1378 | (57.04) | Reference | <10−3 |
 High school | 314 | (13.02) | 280 | (11.59) | 1.46 [1.22, 1.74] | |
 Middle school | 178 | (7.38) | 195 | (8.07) | 1.19 [0.95, 1.48] | |
 Primary school or lower | 858 | (35.59) | 563 | (23.30) | 1.98 [1.73, 2.26] | |
Occupation | ||||||
 Employed | 1682 | (69.88) | 1897 | (78.58) | Reference | <10−3 |
 Self-employed | 262 | (10.89) | 184 | (7.62) | 1.61 [1.32, 1.96] | |
 Unemployed | 463 | (19.24) | 333 | (13.80) | 1.57 [1.34, 1.83] | |
Personal annual income (RMB) | ||||||
 <50,000 | 1165 | (48.32) | 1093 | (45.24) | Reference | 0.13 |
 50,000-100,000 | 777 | (32.23) | 841 | (34.81) | 0.87 [0.76, 0.99] | |
 > 100,000 | 469 | (19.45) | 482 | (19.95) | 0.91 [0.79, 1.06] | |
Smokingb | ||||||
 None smoker | 2298 | (95.31) | 2294 | (96.18) | Reference | 0.41 |
 Occasional smoker | 63 | (2.61) | 57 | (2.39) | 1.10 [0.77, 1.59] | |
 Regular smoker | 50 | (2.07) | 34 | (1.43) | 1.47 [0.95, 2.28] | |
Institutionsc | ||||||
 1 | 1404 | (58.23) | 1409 | (58.32) | Reference | 1.00 |
 2 | 276 | (11.45) | 274 | (11.34) | 1.01 [0.84, 1.21] | |
 3 | 291 | (12.07) | 293 | (12.13) | 1.00 [0.83, 1.19] | |
 4 | 272 | (11.28) | 272 | (11.26) | 1.00 [0.84, 1.21] | |
 5 | 168 | (6.97) | 168 | (6.95) | 1.00 [0.80, 1.26] |