Table 1.
Comparison of SWS mother-child pairs with complete data with those lacking either maternal body composition or 6-year follow-up data but born in the same time period.
| Participating mother-child pairs (n= 940) |
Mother-child pairs with missing data (n=589) |
P-value | ||
|---|---|---|---|---|
| Maternal characteristics | ||||
| Age at child's birth, years (mean (SD)) | 30.3 (3.8) | 29.7 (3.8) | 0.007 | |
| Primiparous (n (%)) | ||||
| No | 494 (52.6) | 355 (60.3) | 0.003 | |
| Yes | 446 (47.5) | 234 (39.7) | ||
| Qualifications (n (%)) |
None | 15 (1.6) | 36 (6.1) | <0.001 |
| GCSE D-G | 88 (9.4) | 67 (11.4) | ||
| GCSE A*-C | 278 (29.6) | 165 (28.1) | ||
| A Level | 270 (28.8) | 175 (29.8) | ||
| HND | 66 (7.0) | 39 (6.6) | ||
| Degree | 222 (23.6) | 106 (18.0) | ||
| Parents’ social class (n (%)) |
I | 100 (10.8) | 52 (12.3) | 0.019 |
| II | 454 (48.8) | 178 (42.3) | ||
| IIIN | 263 (28.5) | 112 (26.6) | ||
| IIIM | 72 (7.7) | 51 (12.1) | ||
| IV | 39 (4.2) | 20 (4.8) | ||
| V | 2 (0.2) | 8 (1.9) | ||
| Smoked in pregnancy (n (%)) | ||||
| No | 768 (84.9) | 431 (77.2) | <0.001 | |
| Yes | 137 (15.1) | 127 (22.8) | ||
| Maternal asthma (n (%)) | ||||
| No | 733 (78.7) | 442 (76.2) | 0.251 | |
| Yes | 198 (21.3) | 138 (23.8) | ||
| Maternal childhood eczema (n (%)) | ||||
| No | 758 (81.5) | 476 (82.1) | 0.783 | |
| Yes | 172 (18.5) | 104 (17.9) | ||
| Maternal rhinitis (n (%)) | ||||
| No | 539 (57.9) | 353 (60.9) | 0.254 | |
| Yes | 392 (42.1) | 227 (39.1) | ||
| Maternal atopy (n (%)) | ||||
| No | 438 (53.0) | 236 (57.0) | 0.185 | |
| Yes | 388 (47.0) | 178 (43.0) | ||
| Height, cm (mean (SD)) | 163.5 (6.6) | 162.7 (6.0) | 0.020 | |
| BMI, kg/m2 (median, (IQR)) | 24.3 (22.0 -27.5) | 24.1 (21.8 -27.4) | 0.657 | |
| Fat mass, kg (median, (IQR)) | 20.3 (16.3 -25.9) | 19.5 (15.7 -25.8) | 0.116 | |
| Child’s characteristics | ||||
| Gender (n (%)) | ||||
| Male | 485 (51.6) | 313 (53.4) | 0.489 | |
| Female | 455 (48.4) | 273 (46.6) | ||
| Birth weight, kg (mean (SD)) | 3.440 (0.551) | 3.420 (0.580) | 0.615 | |
| Gestational age, weeks (median (IQR)) | 40.1 (39.0 -41.0) | 40.0 (39.1 -41.0) | 0.969 | |
| Mother smoked during child’s infancy (n (%)) |
||||
| No | 768 (84.9) | 431 (77.2) | <0.001 | |
| Yes | 137 (15.1) | 125 (22.8) | ||
Numbers do not always add to the full column totals due to missing data
Binary outcomes were compared by χ2 test, categorical outcomes by a χ2 test for trend, and continuous variables using t-tests, after transformation where appropriate, or a ranksum test.