Table 5. Association of semen parameters with volume, sperm concentration, motility, mobility, and normal morphology.

A multiple regression model was used to estimate the P-value, and the regression model was adjusted by the age of the participants. A P-value of <0.05 is considered significant, whereas for the covariate, P < 0.10 is considered as potential effect in the regression model.

^*Others (globozoospermia, cryptozoospermia, teratozoospermia, hypo + oligo, hyper + oligo, hyperspermia).

Semen parameters	Volume (mL)		Sperm concentration (millions/mL)		Motility (%)		Mobility (%)		Normal morphology
	β-(95% CI)	P	β-(95% CI)	P	β-(95% CI)	P	β-(95% CI)	P	β-(95% CI)	P
Normozospermia	Ref.		Ref.		Ref.		Ref.		Ref.
Oligozoospermia	0.26 (0.05-0.46)	0.016	-65 (-69 to -61)	<0.001	-11.8 (-13 to -11)	<0.001	-9.10 (-10.9 to -7.27)	<0.001	-2.22 (-2.54 to -1.90)	<0.001
Asthenozooepermia	0.24 (-0.09 to 0.56)	0.156	-33 (-38 to -27)	<0.001	-30 (-32 to -28)	<0.001	-14 (-16 to -11)	<0.001	-2.64 (-3.14 to -2.15)	<0.001
OAT	0.41 (0.24 to 0.58)	<0.001	-68 (-71 to -65)	<0.001	-29 (-30 to -28)	<0.001	-12 (-13 to -10)	<0.001	-3.97 (-4.23 to -3.72)	<0.001
Azoospermia	0.14 (-0.06 to 0.34)	0.174	-71 (-75 to -68)	<0.001	-41 (-43 to -40)	<0.001	-23 (-25 to -22)	<0.001	-6.72 (-7.02 to -6.42)	<0.001
Hypospermia	0.20 (0.004 to 0.40)	0.046	-7.13 (-10.6 to -3.64)	<0.001	0.43 (-0.71 to 1.56)	0.461	-4.43 (-6.15 to -2.72)	<0.001	-0.21 (-0.51 to 0.09)	0.165
Others*	-0.19 (-0.62 to 0.23)	0.368	-15.5 (-23 to -8.10)	<0.001	-3.89 (6.31 to -1.48)	0.002	-4.52 (-8.18 to -0.87)	0.015	-1.05 (-1.70 to -0.40)	0.002
Age (years)	0.01 (0.002 to 0.02)	0.013	0.13 (-0.02 to 0.28)	0.089	-3.89 (-0.07 to -1.48)	0.433	-0.01 (-0.08 to 0.06)	0.798	0.01 (-0.002 to 0.02)	0.085