Table 3.
Associations of maternal smoking during pregnancy and maternal early pregnancy overweight (BMI ≥25.0) with offspring BMI z-score trajectories
| Sex-adjusted model* | ||||
|---|---|---|---|---|
| Maternal smoking during pregnancy | Maternal early pregnancy BMI (kg/m2) | |||
| BMI z-score trajectories | No (n=750) | Yes (n=213) | <25.0 (n=636) | ≥25.0 (n=327) |
| Normal (Reference), n (%) | 550 (73.3) | 132 (62.0) | 483 (75.9) | 199 (60.9) |
| Early persistent obesity, n (%) | 27 (3.6) | 12 (5.6) | 17 (2.8) | 22 (6.7) |
| RR (95% CI) | 1.00 | 1.83 (1.02 to 3.49) | 1.00 | 2.84 (1.54 to 5.25) |
| p Value | 0.044 | <0.001 | ||
| Delayed overweight, n (%) | 80 (10.7) | 34 (16.0) | 53 (8.3) | 61 (18.7) |
| RR (95% CI) | 1.00 | 1.61 (1.13 to 2.28) | 1.00 | 2.32 (1.66 to 3.25) |
| p Value | 0.008 | <0.001 | ||
| Early transient overweight, n (%) | 93 (12.4) | 35 (16.4) | 83 (13.1) | 45 (13.8) |
| RR (95% CI) | 1.00 | 1.41 (0.93 to 2.01) | 1.00 | 1.28 (0.92 to 1.77) |
| p Value | 0.076 | 0.144 | ||
| Adjusted model† | ||||
| Maternal smoking during pregnancy | Maternal early pregnancy BMI (kg/m2) | |||
| BMI z-score trajectories | No (n=657) | Yes (n=164) | <25.0 (n=543) | ≥25.0 (n=278) |
| Normal (Reference), n (%) | 474 (72.2) | 100 (61.0) | 409 (75.3) | 165 (59.4) |
| Early persistent obesity, n (%) | 19 (2.9) | 9 (5.5) | 12 (2.2) | 16 (5.8) |
| RR (95% CI) | 1.00 | 2.16 (1.02 to 4.68) | 1.00 | 3.16 (1.52 to 6.58) |
| p Value | 0.041 | 0.002 | ||
| Delayed overweight, n (%) | 79 (12.0) | 28 (17.1) | 49 (9.0) | 58 (20.8) |
| RR (95% CI) | 1.00 | 1.69 (1.15 to 2.49) | 1.00 | 2.45 (1.73 to 3.46) |
| p Value | 0.008 | <0.001 | ||
| Early transient overweight, n (%) | 85 (12.9) | 27 (16.4) | 73 (13.5) | 39 (14.0) |
| RR (95% CI) | 1.00 | 1.35 (0.90 to 2.00) | 1.00 | 1.25 (0.88 to 1.77) |
| p Value | 0.144 | 0.215 | ||
*Model included the flowing variables: maternal smoking during pregnancy, maternal early pregnancy BMI, and sex.
†Model included the following variables: maternal smoking during pregnancy, maternal early pregnancy BMI, sex, birth weight, gestational age at birth, maternal age at delivery, duration of breastfeeding, maternal education and socioeconomic status.
BMI, Body Mass Index; n, number; RR, Risk ratio.