Estimated effects on birth weight in grams
| Wales | Denmark | |
| Gestational age (95% CI) (g per week) | 139.58 (137.86 to 141.21) | 141.42 (140.85 to 142.2) |
| CF direct (95% CI) | −127.24 (−182 to –72.61) | −116.09 (−152.53 to –80.5) |
| CF indirect (95% CI) | −82.85 (−122.22 to –44.91) | −62.71 (−84.47 to –39.96) |
| CF total (95% CI) | −210.08 (−281.97 to –141.5) | −178.8 (−225.43 to –134.47) |
| First-born=yes (95% CI) | −115.21 (−117.84 to –112.54) | −113.57 (−115.38 to –112.45) |
| Sex=male (95% CI) | 133.18 (130.34 to 135.91) | 133.92 (132.49 to 135.34) |
| WIMD (95% CI)* | ||
| 1 | −114.34 (−118.59 to –109.94) | NA |
| 2 | −71.09 (−75.33 to –66.99) | NA |
| 3 | −39.73 (−44.15 to –35.34) | NA |
| 4 | −19.24 (−24.01 to –14.68) | NA |
| Maternal education (95% CI)† | ||
| Lower secondary education, second stage of basic education | NA | 0.54 (−7.08 to 8.48) |
| Upper secondary education | NA | 86.16 (78.48 to 93.76) |
| Postsecondary non-tertiary education | NA | 113.15 (71.9 to 155.69) |
| First stage of tertiary education, not advanced research qualification | NA | 124.25 (116.21 to 131.96) |
| Second stage of tertiary education, advanced research qualification | NA | 142.84 (124.75 to 159.22) |
| Not known | NA | −32.11 (−52.59 to –10.55) |
*WIMD, where 1=most deprived and 5=least deprived, reference level WIMD=5.
†Reference level Maternal education= Primary education, first stage of basic education .
CF, cystic fibrosis; NA, not available; WIMD, Welsh Index of Multiple Deprivation.