Skip to main content

Table 4 Odds ratios (OR) for a male birth among offspring from parents in the Michigan Long-Term PBB Study with enrollment serum PCB concentrations

From: A cohort study of the association between secondary sex ratio and parental exposure to polybrominated biphenyl (PBB) and polychlorinated biphenyl (PCB)

   N (%) Crude^ Unadjusted * Adjusted**
Exposure Variables (μg/L)   Offspring OR (95% CI) OR (95% CI) OR (95% CI)
Model 1 (Maternal PCB only):     
   Maternal PCB   790    
   < 6   444 (56) 1.00 1.00 1.00
   ≥ 6   346 (44) 1.02 (0.77, 1.35) 0.99 (0.76, 1.30) 1.01 (0.77, 1.32)
Model 2 (Paternal PCB only):     
   Paternal PCB   253    
   < 8   141 (56) 1.00 1.00 1.00
   ≥ 8   112 (44) 1.06 (0.64, 1.75) 1.23 (0.83, 1.82) 1.24 (0.81, 1.88)
Model 3 (Maternal and Paternal PCB combined):   
Maternal PCB Paternal PCB 253    
< 6 < 8 80 (32) 1.00 1.00 1.00
other combinations 116 (46) 1.26 (0.71, 2.22) 1.23 (0.77, 1.97) 1.00 (0.63, 1.57)
≥ 6 ≥ 8 57 (22) 1.13 (0.57, 2.24) 1.39 (0.81, 2.40) 1.53 (0.93, 2.52)
  1. ^ Crude ORs are unadjusted for covariates or offspring born to the same mother or father
  2. * ORs are unadjusted for covariates, but adjusted for offspring born to the same mother or father
  3. ** AORs are adjusted for covariates (Model 1 adjusted for year of offspring's birth; Models 2 and 3 adjusted for year of offspring's birth and paternal BMI as low and normal vs. high) and adjusted for offspring born to the same mother or father