| |
Categories of serum vitamin D
|
|---|
|
Deficient (< 10 ng/ml)
|
Insufficient (10–20 ng/ml)
|
Sufficient (> 20 ng/ml)
|
P trend
|
|---|
|
Semen volume (mL)
|
|
Crude
|
Ref
|
0.004 (-0.59, 0.60)
|
0.67 (0.10, 1.24)
|
0.006
|
|
Model 1
|
Ref
|
-0.05 (-0.66, 0.55)
|
0.63 (0.05, 1.20)
|
0.008
|
|
Model 2
|
Ref
|
-0.006 (-0.61, 0.60)
|
0.62 (0.04, 1.19)
|
0.010
|
|
Model 3
|
Ref
|
0.03 (-0.57, 0.64)
|
0.63 (0.06, 1.20)
|
0.010
|
|
Sperm count (106/mL)
|
|
Crude
|
Ref
|
7.32 (-3.19, 17.85)
|
11.83 (1.84, 21.82)
|
0.021
|
|
Model 1
|
Ref
|
8.57 (-2.02, 19.16)
|
12.71 (2.70, 22.72)
|
0.015
|
|
Model 2
|
Ref
|
10.03 (-0.49, 20.56)
|
13.23 (3.32, 23.13)
|
0.013
|
|
Model 3
|
Ref
|
9.99 (-0.43, 20.42)
|
14.40 (4.56, 24.25)
|
0.005
|
|
Sperm total motility (%)
|
|
Crude
|
Ref
|
13.39 (7.36, 19.43)
|
18.31 (12.59, 24.04)
|
< 0.001
|
|
Model 1
|
Ref
|
13.57 (7.48, 19.66)
|
18.44 (12.68, 24.20)
|
< 0.001
|
|
Model 2
|
Ref
|
13.82 (7.72, 19.92)
|
18.32 (12.58, 24.06)
|
< 0.001
|
|
Model 3
|
Ref
|
13.60 (7.51, 19.69)
|
18.12 (12.37, 23.86)
|
< 0.001
|
|
Normal morphology (%)
|
|
Crude
|
Ref
|
1.21 (0.26, 2.16)
|
2.22 (1.31, 3.12)
|
< 0.001
|
|
Model 1
|
Ref
|
0.93 (-0.005, 1.87)
|
2.02 (1.13, 2.91)
|
< 0.001
|
|
Model 2
|
Ref
|
1.02 (0.09, 1.95)
|
2.00 (1.12, 2.88)
|
< 0.001
|
|
Model 3
|
Ref
|
1.05 (0.12, 1.98)
|
1.95 (1.07, 2.83)
|
< 0.001
|
- Data are presented as β (95 % confidence interval)
- †P < 0.05 was considered statistically significant
- Crude: Unadjusted
- Model 1: Adjusted for age
- Model 2: Model 1 + educational status, smoking, alcohol consumption, job, and varicocele
- Model 3: Model 2 + body mass index and total energy intake
