Table 3. The association between weight gain in the first 4 months and BMI z-score and overweight or obesity at age 2–4 years and 5–7 years.
| Weight gain category | N |
BMI z-score |
Overweight or obesity | ||
|---|---|---|---|---|---|
| mean ± SD | β(95%CI) | Case, No. (%) | OR(95%CI) | ||
| Age 2–4 years | |||||
| On track | 706 | 0.51 ± 1.33 | ref | 237(33.6) | 1.0 |
| Slow growth | 412 | 0.36 ± 1.38 | −0.35(−0.50, −0.20)§ | 128(31.1) | 0.7(0.5, 0.9)‡ |
| Rapid growth | 294 | 0.69 ± 1.26 | 0.43(0.26, 0.61)§ | 112(38.1) | 1.8(1.3, 2.4)§ |
| Extremely rapid | 516 | 0.86 ± 1.34 | 0.76(0.60, 0.92)§ | 239(46.3) | 3.3(2.5, 4.4)§ |
| Weight gain z-score | 0.32(0.28, 0.37)§ | 1.6(1.5, 1.8)§ | |||
| Age 5–7 years | |||||
| On track | 468 | 0.68 ± 1.20 | ref | 199(42.5) | 1.0 |
| Slow growth | 283 | 0.60 ± 1.26 | −0.20(−0.37, −0.04)† | 102(36.0) | 0.6(0.4, 0.9)‡ |
| Rapid growth | 192 | 0.94 ± 1.11 | 0.46(0.27, 0.65)§ | 91(47.4) | 1.7(1.2, 2.4)‡ |
| Extremely rapid | 336 | 1.05 ± 1.18 | 0.62(0.44, 0.79)§ | 171(50.9) | 2.1(1.5, 3.0)§ |
| Weight gain z-score | 0.24(0.19, 0.29)§ | 1.5(1.3, 1.6)§ | |||
Gestational age category was defined as full term (gestational age ≥39 weeks), early term (37–38 weeks), late preterm (34–36 weeks), and early preterm (<34 weeks). Weight gain z-score was defined as the change in weight for age z–score between birth and 4 months and was categorized into four groups: slow (weight gain z-score less than −0.67); on track (weight gain z-score between −0.67 and 0.67), rapid (weight gain z-score between 0.67 and 1.28), and extremely rapid (weight gain z-score more than 1.28).
Adjusted for maternal education, race, smoking, parity, prepregnancy BMI category, hypertensive disorders, diabetes, fetal growth status, gestational age categories, and breastfeeding status.
†P < 0.05; ‡P < 0.01; §P < 0.001.