Table 4.

Hazard Ratios of Time to Pregnancy with Live Birth by Antioxidant Intake and Age

Age < 35 y (n=273)
Antioxidant a,b HR (95% CI)	Dietary Supplement Intake, Alone	Dietary Intake				Total Nutrient Intakec
		T1	T2	T3	p-trend	T1	T2	T3	p-trend
β-carotene	--	1.00	0.98 (0.67, 1.44)	1.26 (0.86, 1.84)	0.17	1.00	0.96 (0.65, 1.41)	1.18 (0.81, 1.72)	0.38
Continuous	1.19 (1.01, 1.41)	1.08 (0.96, 1.23)	--	--		1.11 (1.00, 1.23)	--	--
Vitamin C	--	1.00	1.01 (0.69, 1.48)	0.91) (0.62, 1.33)	0.60	1.00	1.00 (0.68, 1.47)	1.19 (0.82, 1.74)	0.36
Continuous	1.10 (1.02, 1.18)	0.94 (0.77, 1.13)				1.07 (1.00, 1.15)
Vitamin E	--	1.00	0.88 (0.60, 1.29)	0.82 (0.56, 1.20)	0.32	1.00	1.06 (0.72, 1.56)	1.15 (0.79, 1.66)	0.48
Continuous	0.95 (0.87, 1.04)	0.94 (0.28, 3.14)	--	--		0.95 (0.87, 1.04)	--	--
Age ≥ 35 y (n=154)
Antioxidant a,b HR (95% CI)	Dietary Supplement Intake, Alone	Dietary Intake				Total Nutrient Intakec
		T1	T2	T3	p-trend	T1	T2	T3	p-trend
β-carotene	--	1.00	0.87 (0.54, 1.41)	0.58 (0.34, 0.96)	0.03	1.00	0.77 (0.48, 1.25)	0.56 (0.34, 0.92)	0.02
Continuous	1.23 (0.99, 1.51)	0.82 (0.66, 1.00)				0.91 (0.77, 1.08)
Vitamin C	--	1.00	1.05 (0.63, 1.74)	1.22 (0.75, 1.97)	0.42	1.00	1.06 (0.64, 1.74)	0.86 (0.53, 1.42)	0.46
Continuous	1.03 (0.97, 1.09)	1.11 (0.88, 1.39)				1.03 (0.97, 1.09)
Vitamin E	--	1.00	0.82 (0.50, 1.36)	0.99 (0.61, 1.61)	0.95	1.00	0.98 (0.60, 1.61)	0.84 (0.52, 1.37)	0.54
Continuous	1.07 (1.01, 1.13)	0.81 (0.10, 6.45)				1.07 (0.97, 1.13)

^aadjusted for treatment group, body mass index, and total energy.

^bfor continuous analyses: per unit increase typical for a pre-natal vitamin supplement; β-carotene: 2000 IU, Vitamin C: 60mg, Vitamin E: 20 mg;

^ccombined dietary and dietary supplement sources.