Table 1.
Mother-offspring pairs characteristics (n=209)
| Variables | All (n=209) |
Boys (n=115) |
Girls (n=94) |
p-value | |||
|---|---|---|---|---|---|---|---|
| Maternal age, years | 29.5 | ± 3.6 | 29.4 | ± 3.6 | 29.7 | ± 3.6 | 0.5269 |
| Maternal race, n (%) | 0.1636 | ||||||
| Caucasian | 177 | (84.7) | 101 | (87.8) | 76 | (80.9) | |
| AA/Asian/Hispanic/Mixed race/Unknown | 32 | (15.3) | 14 | (12.2) | 18 | (19.1) | |
| Maternal education, n (%) | 0.7432 | ||||||
| High school or GED | 13 | (6.2) | 9 | (7.8) | 4 | (4.3) | |
| Partial college or graduate | 127 | (60.8) | 68 | (59.1) | 59 | (62.8) | |
| Graduate training or degree | 63 | (30.1) | 35 | (30.4) | 28 | (29.8) | |
| Specialized training | 6 | (2.9) | 3 | (2.6) | 3 | (3.2) | |
| Maternal % FM | 35.7 | ± 7.4 | 35.7 | ± 6.9 | 35.7 | ± 7.9 | 0.9900 |
| Annual family income n (%) | 0.2225 | ||||||
| ≤ $60,000 | 85 | (40.7) | 52 | (45.2) | 33 | (35.1) | |
| > $60,000-$90,000 | 62 | (29.7) | 29 | (25.2) | 33 | (35.1) | |
| ≥ $90,000 | 62 | (29.7) | 34 | (29.6) | 28 | (29.8) | |
| Maternal total AC/day × 1000 | 320 | ± 121 | 318 | ± 138 | 323 | ± 96 | 0.7904 |
| Maternal REE, kcal/day0.70 | 87.7 | ± 8.9 | 87.9 | ± 8.7 | 87.4 | ± 9.2 | 0.6745 |
| Maternal RER | 0.85 | ± 0.04 | 0.85 | ± 0.04 | 0.85 | ± 0.04 | 0.8478 |
| GWG, kg | 11.8 | ± 4.1 | 12.2 | ± 3.8 | 11.3 | ± 4.5 | 0.1213 |
| IOM recommendations for GWG, n (%) | 0.0589 | ||||||
| Below | 28 | (13.4) | 10 | (8.7) | 18 | (19.1) | |
| Ideal | 107 | (51.2) | 65 | (56.5) | 42 | (44.7) | |
| Above | 74 | (35.4) | 40 | (34.8) | 34 | (36.2) | |
| Gestational age, wks. | 39.3 | ± 0.9 | 39.3 | ± 0.9 | 39.2 | ± 0.8 | 0.8891 |
| Delivery method, n (%) | 0.1427 | ||||||
| Vaginal induced | 58 | (27.8) | 38 | (33.0) | 20 | (21.3) | |
| Vaginal not induced | 77 | (36.8) | 41 | (35.7) | 36 | (38.3) | |
| C-section | 74 | (35.4) | 36 | (31.3) | 38 | (40.4) | |
| Birth weight, (kg) | 3.5 | ±± 0.5 | 3.6 | ± 0.5 | 3.5 | ± 0.5 | 0.0228 |
| Birth Length, (cm) | 51.0 | ± 2.6 | 51.4 | ± 2.5 | 50.6 | ± 2.6 | 0.0123 |
| Weight-for-age z-score at birth |
0.45 | ± 0.98 | 0.47 | ± 0.96 | 0.42 | ± 1.00 | 0.7357 |
| Length-for-age z-score at birth |
0.79 | ± 1.35 | 0.82 | ± 1.32 | 0.76 | ± 1.39 | 0.7136 |
| BMI-for-age z-score at birth | 0.06 | ± 1.14 | 0.07 | ± 1.12 | 0.05 | ± 1.17 | 0.9272 |
| Feeding mode, n (%) | 0.3430 | ||||||
| Formula or mixed fed | 62 | (29.7) | 31 | (27.0) | 31 | (33.0) | |
| Breast fed only | 147 | (70.3) | 84 | (73.0) | 63 | (67.0) | |
| Length at age 2 wks, (cm) | 51.3 | ± 2.0 | 51.7 | ±1.9 | 50.8 | ± 2.0 | 0.0015 |
| Weight at age 2 wks, (kg) | 3.7 | ± 0.5 | 3.8 | ±0.5 | 3.6 | ± 0.4 | 0.0022 |
| Length z-score at age 2 wks | -0.34 | ± 1.01 | −0.33 | ± 0.98 | −0.35 | ± 1.06 | 0.8898 |
| Weight z-core at age 2 wks | 0.01 | ± 0.86 | 0.01 | ± 0.89 | 0.01 | ± 0.83 | 0.9347 |
| Weight for length z-score at age 2 weeks |
0.11 | ± 0.90 | 0.13 | ± 0.87 | 0.08 | ± 0.94 | 0.6792 |
| Offspring % FM at age 2 wks | 13.0 | ± 3.5 | 12.5 | ± 3.4 | 13.6 | ± 3.6 | 0.0295 |
Data presented as mean±SD, counts and %. AA=African American; GED=general education development; AC=activity counts; REE=resting energy expenditure; RER=respiratory exchange ratio; GWG=gestational weight gain; IOM=Institute of Medicine