Table I.
Demographics of infancy subgroups at 3 and 12 months of age
| All 3 months (N = 241), mean ± SD | 3-month breast-fed (N = 81), mean ± SD | 3-month formula-fed (N = 84), mean ± SD | |
|---|---|---|---|
| Sex (% male) | 46% | 42% | 46% |
| Gestational age (wk) | 39.9 ± 1.5 | 40.2 ± 1.3 | 39.8 ± 1.5 |
| Birth weight (kg) | 3.50 ± 0.52 | 3.54 ± 0.43 | 3.50 ± 0.57 |
| 3 m weight (kg) | 6.13 ± 0.80 | 5.96 ± 0.66 | 6.38 ± 0.76∗ |
| 3 m weight SDS | −0.07 ± 1.05 | −0.19 ± 0.88 | 0.25 ± 0.96∗ |
| All 12 mo (N = 141), mean ± SD | 12 mo initially breast-fed (N = 38), mean ± SD | 12 mo initially formula-fed (N = 50), mean ± SD | |
|---|---|---|---|
| Sex (% male) | 55% | 47% | 56% |
| Gestational age (wk) | 40.0 ± 1.4 | 40.1 ± 1.2 | 39.9 ± 1.4 |
| Birth weight (kg) | 3.47 ± 0.52 | 3.58 ± 0.43 | 3.43 ± 0.62 |
| 12 m weight (kg) | 10.03 ± 1.31 | 9.72 ± 1.26 | 10.32 ± 1.41∗ |
| 12 m weight SDS | 0.07 ± 1.21 | −0.19 ± 1.20 | 0.34 ± 1.24∗ |
∗
P < .05 between breast-fed and formula-fed infants.