Table 2.

Correlation between antioxidant levels and semen parameters adjusting for covariates at baseline (visit 1). Adjusted for covariates: Male: age, race, BMI, smoking, marijuana, alcohol; Women: age, BMI; Couple: duration of infertility, previous pregnancy, annual household income, insurance coverage, marital status. Partial correlation statistics were used to describe the relationship between two variables when controlling for the effects of one more variables in this relationship

Antioxidant level	Concentration	Motility	DNA fragmentation	Total motile
Vitamin E	0.14 (P = 0.15) N = 110	0.02 (P = 0.84) N = 110	0.08 (P = 0.49) N = 99	0.09 (P = 0.37) N = 110
Selenium	− 0.17 (P = 0.10) N = 106	− 0.07 (P = 0.47) N = 106	− 0.03 (P = 0.76) N = 95	− 0.14 (P = 0.16) N = 106
Zinc	− 0.01 (P = 0.89) N = 107	0.02 (P = 0.83) N = 107	N = 97	− 0.03 (P = 0.77) N = 107