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. Author manuscript; available in PMC: 2015 Mar 1.
Published in final edited form as: Fertil Steril. 2013 Dec 17;101(3):759–766. doi: 10.1016/j.fertnstert.2013.11.008

Table 3.

Hazard Ratios of Time to Pregnancy (TTP) with Live Birth by Antioxidant Intake and BMI

BMI < 25 m2 / kg (n=319)
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 1.09
(0.78, 1.53)		 0.92
(0.65, 1.31)		 0.57 1.00 0.86
(0.61, 1.20)		 0.86
(0.61, 1.20)		 0.36
  Continuous 1.19
(0.96, 1.48)		 1.00
(0.87, 1.15)		 -- -- 1.03
(0.91, 1.17)		 -- --
Vitamin C -- 1.00 0.93
(0.66, 1.32)		 0.95
(0.68, 1.32)		 0.77 1.00 1.05
(0.74, 1.50)		 1.13
(0.80, 1.59)		 0.49
  Continuous 1.09
(1.03, 1.15)		 0.98
(0.83, 1.17)		 1.08
(1.03, 1.14)
Vitamin E -- 1.00 0.84
(0.60, 1.18)		 0.73
(0.52, 1.03)		 0.35 1.00 1.01
(0.71, 1.44)		 1.01
(0.72, 1.42)		 0.94
  Continuous 1.00
(0.95, 1.05)		 0.71
(0.18, 2.75)		 -- -- 1.00
(0.95, 1.05)		 -- --
BMI ≥ 25 m2 / kg (n=115)
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 0.76
(0.38, 1.51)		 1.21
(0.64, 2.29)		 0.34 1.00 1.23
(0.61, 2.46)		 1.44
(0.74, 2.79)		 0.28
  Continuous 1.29 (1.09, 1.53) 1.02 (0.86, 1.21) 1.10
(0.96, 1.26)
Vitamin C -- 1.00 1.11
(0.57, 2.15)		 1.40
(0.73, 2.69)		 0.29 1.00 1.05
(0.56, 1.99)		 1.14
(0.61, 2.16)		 0.67
  Continuous 1.00
(0.91, 1.10)		 1.02
(0.77, 1.35)		 1.00
(0.94, 1.09)
Vitamin E -- 1.00 0.93
(0.50, 1.73)		 1.06
(0.58, 1.95)		 0.81 1.00 1.38
(0.72, 2.64)		 1.28
(0.68, 2.42)		 0.48
  Continuous 1.07
(0.97, 1.17)		 1.44
(0.28, 7.50)		 1.07
(0.97, 1.17)
a

adjusted for treatment group, age, and total energy.

b

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

c

ombined dietary and dietary supplement sources.