Table 6 Associations between total seafood intake and the subcategories late preterm delivery (35 to <37 w), moderately preterm delivery (32 to <34 w) and early preterm delivery (22 to <32 w). N = 67,007 mothers in the Norwegian Mother and Child Cohort Study (MoBa) 2002–2008
| Â | All | PTD | Unadjusted | Adjusted |
|---|---|---|---|---|
n (%) | HRa (95% CI) | HRb (95% CI) | ||
Late PTD (35 to <37 w) | Â | 2659 (4.0) | Â | Â |
Total seafood intake | ||||
  ≤ 5 g/d (never/rarely) | 2903 | 157 (5.4) | 1 | 1 |
  > 5–20 g/d (<1 serving/week) | 12,111 | 525 (4.3) | 0.80 (0.67, 0.95) | 0.82 (0.68, 0.98) |
  > 20–40 g/d (1–2 servings/week) | 26,684 | 1079 (4.0) | 0.74 (0.63, 0.88) | 0.78 (0.66, 0.92) |
  > 40–60 g/d (2–3 servings/week) | 16,194 | 586 (3.6) | 0.66 (0.55, 0.79) | 0.69 (0.58, 0.83) |
  > 60 g/d (≥3 servings/week) | 8144 | 312 (3.8) | 0.70 (0.58, 0.85) | 0.71 (0.58, 0.86) |
  P for trendc |  |  | <0.001 | <0.001 |
LCn-3PUFA from supplements | ||||
 No supplement | 21,676 | 851 (3.9) | 1 | 1 |
  < 0.30 g/d (median 0.16 g/d) | 22,203 | 917 (4.1) | 1.05 (0.96, 1.16) | 1.07 (0.97, 1.18) |
  ≥ 0.30 g/d (median 0.80 g/d) | 22,157 | 891 (4.0) | 1.03 (0.93, 1.13) | 1.04 (0.94, 1.15) |
  P for trendc |  |  | 0.609 | 0.450 |
Moderately PTD (32 to <34w) | Â | 491 (0.7) | Â | Â |
Total seafood intake | ||||
  ≤ 5 g/d (never/rarely) | 2778 | 32 (1.2) | 1 | 1 |
  > 5–20 g/d (<1 serving/week) | 11,680 | 94 (0.8) | 0.70 (0.47, 1.04) | 0.75 (0.50, 1.12) |
  > 20–40 g/d (1–2 servings/week) | 25,784 | 179 (0.7) | 0.60 (0.41, 0.88) | 0.68 (0.47, 0.99) |
  > 40–60 g/d (2–3 servings/week) | 15,730 | 122 (0.8) | 0.67 (0.46, 0.99) | 0.77 (0.52, 1.15) |
  > 60 g/d (≥3 servings/week) | 7896 | 64 (0.8) | 0.70 (0.46, 1.07) | 0.78 (0.51, 1.20) |
  P for trendc |  |  | 0.432 | 0.792 |
LCn-3PUFA from supplements | Â | Â | Â | Â |
 No supplement | 20,987 | 169 (0.8) | 1 | 1 |
  < 0.30 g/d (median 0.16 g/d) | 21,424 | 138 (0.6) | 0.83 (0.66, 1.05) | 0.84 (0.66, 1.06) |
  ≥ 0.30 g/d (median 0.80 g/d) | 21,457 | 191 (0.9) | 1.15 (0.94, 1.42) | 1.19 (0.95, 1.48) |
  P for trendc |  |  | 0.158 | 0.093 |
Early PTD (22 to <32 w) | Â | 480 (0.7) | Â | Â |
Total seafood intake | ||||
  ≤ 5 g/d (never/rarely) | 2777 | 31 (1.1) | 1 | 1 |
  > 5–20 g/d (<1 serving/week) | 11,680 | 94 (0.8) | 0.72 (0.48, 1.08) | 0.77 (0.51, 1.16) |
  > 20–40 g/d (1–2 servings/week) | 25,787 | 182 (0.7) | 0.63 (0.43, 0.92) | 0.71 (0.48, 1.04) |
  > 40–60 g/d (2–3 servings/week) | 15,724 | 116 (0.7) | 0.66 (0.44, 0.98) | 0.75 (0.50, 1.12) |
  > 60 g/d (≥3 servings/week) | 7899 | 57 (0.7) | 0.65 (0.42, 0.99) | 0.68 (0.43, 1.06) |
  P for trendc |  |  | 0.116 | 0.196 |
LCn-3PUFA from supplements | ||||
 No supplement | 21,005 | 180 (0.9) | 1 | 1 |
  < 0.30 g/d (median 0.16 g/d) | 21,438 | 152 (0.7) | 0.83 (0.67, 1.03) | 0.84 (0.67, 1.05) |
  ≥ 0.30 g/d (median 0.80 g/d) | 21,414 | 148 (0.7) | 0.81 (0.65, 1.00) | 0.81 (0.65, 1.01) |
  P for trendc |  |  | 0.049 | 0.072 |