Table 3.
Frequency of Multivitamin Use |
|||||
---|---|---|---|---|---|
Subgroup | Never | ≤ 2 /wk | 3 – 5 / wk | ≥ 6 / wk | P trend * |
All participants | |||||
Cases / non-cases | 224 / 10,926 | 32 / 1,808 | 52 / 3,796 | 127 / 9,783 | |
Relative risk (95% CI) † | 1.00 (referent) | 0.88 (0.60, 1.28) | 0.69 (0.51, 0.95) | 0.59 (0.46, 0.75) | <0.001 |
Not using any contraceptive method | |||||
Cases / non-cases | 128 / 3,872 | 16 / 667 | 25 / 1,548 | 71 / 4,997 | |
Relative risk (95% CI) † | 1.00 (referent) | 0.72 (0.42, 1.24) | 0.50 (0.32, 0.78) | 0.41 (0.29, 0.56) | <0.001 |
Not using hormonal contraception ‡ | |||||
Cases / non-cases | 184 / 8,760 | 25 / 1,524 | 49 / 3,251 | 113 / 8,822 | |
Relative risk (95% CI) † | 1.00 (referent) | 0.80 (0.52, 1.22) | 0.75 (0.54, 1.04) | 0.57 (0.44, 0.73) | <0.001 |
Not using barrier methods § | |||||
Cases / non-cases | 172 / 6,355 | 23 / 998 | 29 / 2,201 | 88 / 6,190 | |
Relative risk (95% CI) † | 1.00 (referent) | 0.82 (0.53, 1.29) | 0.49 (0.33, 0.73) | 0.49 (0.37, 0.65) | <0.001 |
Calculated with the median frequency of use in each category as a continuous variable.
Adjusted for age (continuous), calendar time (4 two-year intervals), total energy intake (continuous), body mass index (<20, 20–24.9, 25–29.9, ≥30 and missing), parity (0, 1, ≥2 and missing), smoking history (never, past 1–4 cig/day, past 5–14 cig/day, past 15–24 cig/day, past ≥ 25 cig/day or unknown amount, current 1–4 cig/day, current 5–14 cig/day, current 15–24 cig/day and current ≥ 25 cig/day or unknown amount), physical activity (<3 MET-h/wk, 3–8.9 MET-h/wk, 9–17.9 MET-h/wk, 18–26.9 MET-h/wk, 27–41.9 METh/wk, ≥ 42 MET-h/wk and missing), and intakes of alcohol (no intake, < 2 g/day, 2–4.9 g/day, ≥ 5 g/day), coffee (<1 serving/month, 1 serving/month, 2–6 servings/week, 1 serving/day, 2–3 servings/day, ≥ 4 servings/day) major types of fatty acids and protein. The model including all participants regardless of recent contraception also includes terms for recency of contraceptive use (current user, never user, past user 0–23 months ago, past user 24–47 months ago, past user 48–71 months ago, past user 72–95 months ago, past user 96–119 months ago, past user ≥ 120 months ago and missing).
Oral contraceptives and injected or implantable progestins
Condoms, diaphragms or cervical caps.