Table 3.
Urinary iodine concentration (µg/L (UIC)) and urinary iodine to creatinine ratio (µg iodine/g creatinine (UI/Cr ratio)) according to selected maternal dietary intake given as median with 25th and 75th percentiles in the study population.
| n | UIC (µg/L) | p-Value * | UI/Cr Ratio (µg/g) | p-Value * | |
|---|---|---|---|---|---|
| Dietary factors | |||||
| Seafood dinner | 934 | 0.539 | 0.103 | ||
| <2 portions/week | 653 | 78 (48–130) | 82 (51–126) | ||
| ≥2 portions/week | 281 | 80 (47–125) | 88 (57–129) | ||
| Egg | 821 | 0.430 | 0.156 | ||
| <3 eggs/week | 701 | 80 (49–130) | 82 (53–127) | ||
| ≥3 eggs/week | 120 | 78 (36–140) | 92 (55–145) | ||
| Dairy products | 806 | <0.0001 | <000.1 | ||
| 0–1 portion/day | 153 | 57 a (39–110) | 64 a (45–110) | ||
| 2–3 portion/day | 524 | 83 b (48–130) | 83 b (55–130) | ||
| 4–9 portions/day | 128 | 99 b (59–168) | 105 c (77–150) | ||
| Iodine supplement use | 948 | <0.0001 | <0.0001 | ||
| Yes (≥5 times/week) | 144 | 120 a (72–208) | 140 a (84–233) | ||
| No (<5 times/week) | 804 | 75 b (44–120) | 78 b (51–116) |
Different letters indicate statistical differences. * p-value for differences between groups using Mann–Whitney U to compare two groups or Kruskall–Wallis test comparing categories with more than two groups.