Table 3 Association between paternal factors and Preterm births by multiple logistic regression analysis
From: Paternal factors and adverse birth outcomes in Lanzhou, China
Paternal factors | Term births (N = 9122) (n/%) | Pre-term Briths (N = 999) (n/%) | OR (95%CI)a | OR (95%CI)b |
|---|---|---|---|---|
Age | ||||
  < 25 | 691 (7.6%) | 118 (11.8%) | ref. | ref. |
 25 to < 30 | 3215 (35.2%) | 321 (32.1%) | 0.97 (0.75,1.25) | 1.04 (0.80,1.35) |
 30 to < 35 | 3491 (38.3%) | 330 (33.0%) | 0.85 (0.64,1.13) | 0.93 (0.70,1.23) |
  ≥ 35 | 1725 (18.9%) | 230 (23.0%) | 0.77 (0.55,1.07) | 0.83 (0.60,1.16) |
 p for trend |  |  | 0.166 | 0.355 |
Ethnicity | ||||
 Han | 8410 (92.2%) | 881 (88.2%) | ref. | ref. |
 Others | 712 (7.8%) | 118 (11.8%) | 1.08 (0.76,1.53) | 1.06 (0.74,1.50) |
Education years (%) | ||||
 Less than high school graduation | 1620 (17.8%) | 384 (38.4%) | ref. | ref. |
 high school and community college | 3629 (39.8%) | 361 (36.1%) | 0.58 (0.48,0.71) | 0.60 (0.49,0.73) |
 high than college | 3873 (42.5%) | 254 (25.4%) | 0.53 (0.42,0.69) | 0.55 (0.43,0.71) |
Height (m) | ||||
  < 1.71 | 2767 (30.3%) | 354 (35.4%) | ref. | ref. |
 1.71–1.74 | 2291 (25.1%) | 261 (26.1%) | 1.00 (0.84,1.20) | 1.02 (0.85,1.22) |
  ≥ 1.75 | 4064 (44.6%) | 384 (38.4%) | 0.93 (0.79,1.09) | 0.95 (0.81,1.11) |
 p for trend |  |  | 0.094 | 0.169 |
Weight (Kg) | ||||
  < 67.0 | 2820 (30.9%) | 393 (39.3%) | ref. | ref. |
 67–74.9 | 2534 (27.8%) | 265 (26.5%) | 0.82 (0.69,0.97) | 0.81 (0.67,0.98) |
  ≥ 75 | 3768 (41.3%) | 341 (34.1%) | 0.79 (0.68,0.93) | 0.74 (0.57,0.96) |
 p for trend |  |  | 0.002 | 0.005 |
BMI (kg/m2) | ||||
  < 18.5 | 280 (3.1%) | 37 (3.7%) | 1.03 (0.71,1.48) | 1.00 (0.69,1.45) |
 18.5–23.9 | 4541 (49.8%) | 543 (54.4%) | ref. | ref. |
  ≥ 24 | 4301 (47.2%) | 419 (41.9%) | 0.91 (0.79,1.05) | 0.92 (0.80,1.06) |
 p for trend |  |  | 0.013 | 0.026 |
Smoking cigarettes per day | ||||
 No | 4764 (52.2%) | 467 (46.8%) | ref. | ref. |
 ever smoker | 716 (7.9%) | 86 (8.6%) | 1.07 (0.83,1.39) | 1.05 (0.81,1.350 |
 current smoker | 3642 (39.3%) | 446 (44.6%) | 1.11 (0.95,1.30) | 1.10 (0.93,1.28) |
  ≤ 3 packyears | 1605 (17.6%) | 172 (17.2%) | 0.99 (0.81,1.20) | 0.96 (0.79,1.17) |
 4–6 packyears | 1584 (17.4%) | 185 (18.5%) | 1.08 (0.89,1.30) | 1.06 (0.87,1.28) |
  > 6 packyears | 1169 (12.8%) | 175 (17.5%) | 1.32 (1.08,1.62) | 1.31 (1.07,1.61) |
 p for trend |  |  | 0.051 | 0.065 |
Drinking per year | ||||
 No | 7032 (77.1%) | 796 (79.7%) | ref. | ref. |
 ever drinker | 1515 (16.6%) | 154 (4.9%) | 0.91 (0.75,1.10) | 0.92 (0.76,1.12) |
 current drinker | 575 (6.3%) | 49 (4.9%) | 0.80 (0.58,1.09) | 0.80 (0.59,1.10) |
  ≤ 180 times | 687 (7.5%) | 67 (6.7%) | 0.90 (0.69,1.18) | 0.91 (0.70,1.20) |
 181–440 times | 701 (7.7%) | 56 (5.6%) | 0.71 (0.53,0.96) | 0.71 (0.53,0.96) |
  > 440 times | 702 (7.7%) | 80 (8.0%) | 1.03 (0.80,1.32) | 1.05 (0.81,1.35) |
 p for trend |  |  | 0.828 | 0.878 |
 only red wine | 790 (8.7%) | 66 (6.6%) | 0.77 (0.59,1.01) | 0.79 (0.60,1.03) |
 only white liquor | 438 (4.8%) | 44 (4.4%) | 0.90 (0.65,1.26) | 0.93 (0.66,1.29) |
 only beer | 13 (0.1%) | 2 (0.2%) | 1.02 (0.21,5.03) | 1.04 (0.21,5.19) |
 red wine+ white liquor | 775 (8.5%) | 82 (8.2%) | 0.95 (0.74,1.22) | 0.96 (0.75,1.23) |
 white liquor + beer | 30 (0.2%) | 2 (0.2%) | 0.93 (0.27,3.18) | 0.93 (0.27,3.24) |
 red wine+beer | 20 (0.2%) | 2 (0.20%) | 0.89 (0.20,3.98) | 0.93 (0.21,4.18) |
 red wine+beer+ white liquor | 24 (0.3%) | 4 (0.4%) | 1.22 (0.41,3.65) | 0.93 (0.27,1.23) |