Table 3 Odds ratios (OR) for relationships between preterm birth (PTB) risk and fermented food intake frequency before pregnancy by using logistic regression analysis, Japan Environment and Children’s birth-cohort Study (JECS)
Cases/all (%) | Unadjusted OR (95% CI) | p value | Adjusted OR (95% CI) | p value | |
|---|---|---|---|---|---|
Miso soup, n (%) | |||||
≤ 1 day a week | 367/11,008 (3.33) | Reference | Reference | ||
1–2 days a week | 522/18,207 (2.87) | 0.86 (0.75–0.98) | 0.025 | 0.87 (0.75–1.00) | 0.053 |
3–4 days a week | 643/21,645 (2.97) | 0.89 (0.78–1.01) | 0.073 | 0.92 (0.80–1.06) | 0.228 |
≥ 5 days a week | 811/26,807 (3.03) | 0.91 (0.80–1.03) | 0.117 | 0.93 (0.81–1.06) | 0.285 |
Yogurt, n (%) | |||||
< 1 time a week | 785/25,354 (3.10) | Reference | Reference | ||
1–4 times a week | 1010/33,129 (3.05) | 0.98 (0.90–1.08) | 0.742 | 0.98 (0.89–1.09) | 0.735 |
≥ 5 times a week | 548/19,184 (2.86) | 0.92 (0.82–1.03) | 0.142 | 0.92 (0.82–1.04) | 0.173 |
Cheese, n (%) | |||||
< 1 time a week | 1132/37,567 (3.01) | Reference | Reference | ||
1–2 times a week | 737/23,861 (3.09) | 1.03 (0.93–1.13) | 0.596 | 1.05 (0.95–1.16) | 0.353 |
≥ 3 times a week | 474/16,239 (2.92) | 0.97 (0.89–1.08) | 0.555 | 0.98 (0.87–1.10) | 0.691 |
Fermented soybeans, n (%) | |||||
< 1time a week | 955/30,609 (3.12) | Reference | Reference | ||
1–2 times a week | 813/27,474 (2.96) | 0.95 (0.86–1.04) | 0.260 | 0.96 (0.87–1.06) | 0.443 |
≥ 3 times a week | 575/19,584 (2.94) | 0.94 (0.85–1.04) | 0.242 | 0.96 (0.86–1.08) | 0.525 |