Table 1

Adjusted and crude odds ratios of factors associated with DDH in South Australian singleton live births (1986-93)

VariablesNo of subjectsCrude ORAdjusted OR1-150Coefficients (β) in logisitc regression analysis
Cases (n=1125)Controls (n=146041)OR (95% CI)OR (95% CI)
Mother’s age (yrs):
 <205287251.001.000.0000
 20-24228321691.19 (0.87, 1.63)1.30 (0.96, 1.76)0.2618
 25-2943155721.30 (0.97, 1.76)1.46 (1.09, 1.96)0.3798
 30-34313369671.42 (1.05, 1.93)1.71 (1.26, 2.32)0.5360
 35+101126081.34 (0.95, 1.91)1.72 (1.22,2.44)0.5440
Parity:
0624589762.13 (1.79, 2.52)2.19 (1.83, 2.62)0.7825
 1322510891.27 (1.05, 1.53)1.29 (1.07, 1.56)0.2553
 2+179359761.001.000.0000
Presentation and delivery:
Non-breech presentation8131405331.001.000.0000
 Breech, caesarean delivery25747589.34 (8.07, 10.80)10.03 (8.58, 11.72)2.3058
 Breech, breech delivery5575012.68 (9.46, 16.95)17.15 (12.79, 22.99)2.8420
Baby’s sex:
Female882706023.88 (3.36, 4.48)3.94 (3.41, 4.56)1.3717
 Male243754391.001.000.0000
Region of residence:
 Metropolitan8581024871.56 (1.33, 1.82)1.45 (1.23, 1.69)0.3690
 Outer metropolitan6967511.90 (1.43, 2.52)1.86 (1.41, 2.46)0.6199
 Country198368031.001.000.0000
Oligohydramnios:
 Present62093.74 (1.50, 8.73)3.97 (1.69, 9.35)1.3790
 Absent11191458321.001.000.0000
Birthweight (g):
 <2000 622600.33 (0.13, 0.77)0.30 (0.12, 0.77)−1.1971
 2000-24991744680.48 (0.28, 0.79)0.52 (0.31, 0.88)−0.6469
 2500-2999174217821.00 (0.84, 1.20)0.90 (0.75, 1.08)−0.1066
 3000-3499440552141.001.000.0000
 3500-3999335456270.92 (0.80, 1.07)1.12 (0.97, 1.30)0.1133
 4000-4499124143181.09 (0.89, 1.33)1.55 (1.26, 1.91)0.4367
 4500+2923721.53 (1.03, 2.27)2.67 (1.81, 3.94)0.9819
Gestation (weeks):
<372474280.44 (0.28, 0.67)0.42 (0.25, 0.69)−0.8703
 373159920.70 (0.48, 1.02)0.59 (0.40, 0.86)−0.5299
 38136179931.02 (0.84, 1.24)0.80 (0.66, 0.98)−0.2214
 39224251331.20 (1.03, 1.41)0.90 (0.76, 1.06)−0.1035
 40517698331.001.000.0000
 41161168621.29 (1.08, 1.55)1.26 (1.05, 1.51)0.2311
 42+3228001.54 (1.06, 2.24)1.48 (1.02, 2.13)0.3891
Constant−7.2099
  • 1-150 Logistic regression analysis.