Odds ratios (95%CI) for preterm delivery, low birth weight, and intrauterine growth retardation (IUGR) by quantile of n-3 fatty acid intake. IUGR was defined as having a birth weight below the 10th centile for sex and gestational age
| Birth outcome | Smoking status | n | Quantile of n-3 fatty acid intake from fish | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5* | p§ | |||
| *Highest intake category is the reference category; †adjusted for sex of infant, maternal smoking, age, parity, height, pre-pregnant weight, education and cohabitant status, and alcohol consumption (analyses in non-smokers only not adjusted for smoking status); ‡non-smokers—that is, smoking 0 cigarettes per day at 32 weeks’ gestation; §p for linear trend. | |||||||||
| Preterm birth | |||||||||
| Crude | All | 11585 | 1.05 (0.77 to 1.44) | 1.12 (0.84 to 1.50) | 1.22 (0.91 to 1.62) | 1.17 (0.87 to 1.57) | 0.98 (0.73 to 1.32) | 1.00 | 0.378 |
| NonSm‡ | 9282 | 1.14 (0.79 to 1.65) | 1.18 (0.85 to 1.65) | 1.22 (0.88 to 1.69) | 1.24 (0.89 to 1.73) | 1.01 (0.73 to 1.41) | 1.00 | 0.231 | |
| Adjusted† | All | 10040 | 0.85 (0.59 to 1.22) | 0.95 (0.68 to 1.31) | 1.20 (0.88 to 1.63) | 1.10 (0.80 to 1.51) | 0.93 (0.68 to 1.28) | 1.00 | 0.684 |
| NonSm | 8241 | 1.00 (0.67 to 1.49) | 1.03 (0.72 to 1.49) | 1.19 (0.85 to 1.67) | 1.13 (0.79 to 1.62) | 0.93 (0.65 to 1.33) | 1.00 | 0.649 | |
| Low birth weight | |||||||||
| Crude | All | 11444 | 1.33 (0.95 to 1.87) | 1.46 (1.07 to 1.99) | 1.30 (0.94 to 1.79) | 1.45 (1.05 to 1.99) | 1.03 (0.74 to 1.44) | 1.00 | 0.011 |
| NonSm | 9165 | 1.33 (0.88 to 2.01) | 1.31 (0.90 to 1.91) | 1.26 (0.87 to 1.84) | 1.35 (0.92 to 1.96) | 0.93 (0.63 to 1.38) | 1.00 | 0.041 | |
| Adjusted† | All | 9923 | 1.08 (0.73 to 1.59) | 1.20 (0.84 to 1.72) | 1.33 (0.94 to 1.88) | 1.32 (0.93 to 1.89) | 0.96 (0.66 to 1.39) | 1.00 | 0.311 |
| NonSm | 8140 | 1.11 (0.70 to 1.75) | 1.25 (0.82 to 1.89) | 1.29 (0.87 to 1.91) | 1.27 (0.84 to 1.91) | 0.86 (0.56 to 1.32) | 1.00 | 0.186 | |
| IUGR | |||||||||
| Crude | All | 11444 | 1.69 (1.36 to 2.10) | 1.42 (1.15 to 1.76) | 1.18 (0.95 to 1.47) | 1.19 (0.96 to 1.49) | 1.01 (0.81 to 1.27) | 1.00 | <0.001 |
| NonSm | 9165 | 1.42 (1.08 to 1.88) | 1.23 (0.95 to 1.59) | 1.16 (0.89 to 1.51) | 1.14 (0.88 to 1.50) | 0.98 (0.75 to 1.27) | 1.00 | 0.004 | |
| Adjusted† | All | 9923 | 1.20 (0.93 to 1.55) | 1.06 (0.83 to 1.35) | 1.05 (0.83 to 1.34) | 0.93 (0.72 to 1.19) | 0.94 (0.73 to 1.20) | 1.00 | 0.083 |
| NonSm | 8140 | 1.24 (0.91 to 1.69) | 1.13 (0.85 to 1.51) | 1.13 (0.85 to 1.49) | 1.01 (0.75 to 1.36) | 0.96 (0.73 to 1.28) | 1.00 | 0.083 | |