TABLE 1.
Infant, maternal, and paternal characteristics by term status
| Preterm (n = 26) | Term (n = 97) | P* | |
|---|---|---|---|
| Infant | |||
| Sex, male, N (%) | 16 (61.5) | 49 (50.5) | 0.32 |
| Gestational age, wk | 31.5 (2.7) | 39.8 (1.0) | <0.0001 |
| Birth weight, g | 1723.6 (586.5) | 3539.2 (447.4) | <0.0001 |
| Birth weight z score | −0.03 (0.60) | 0.49 (0.91) | 0.0009 |
| Energy deficit, kcal/kg† | 84.90 (51.50)§ | — | — |
| Protein deficit, g/kg‡ | 1.96 (2.12)‖ | — | — |
| Score for neonatal acute physiology | 8.88 (6.74)¶ | — | — |
| Maternal and paternal | |||
| Maternal age, y | 30.6 (4.8) | 31.1 (4.8) | 0.61 |
| Paternal age, y | 32.4 (4.6) | 33.0 (5.8) | 0.66 |
| Maternal race, white, N (%) | 23 (88.5) | 80 (82.5) | 0.46 |
| Paternal race, white, N (%) | 20 (76.9) | 77 (79.4) | 0.79 |
| Maternal education, N >high school (%) | 17 (65.4) | 82 (84.5) | 0.03 |
| Paternal education, N >high school (%) | 18 (69.2) | 73 (76.0) | 0.48 |
| Maternal weight, prepregnancy, kg | 74.1 (20.3) | 70.6 (16.8) | 0.37 |
| Maternal weight gain, kg | 14.2 (6.4) | 15.3 (5.8) | 0.40 |
| Maternal BMI, kg/m2 | 26.9 (7.9) | 25.9 (6.5) | 0.49 |
| Paternal BMI, kg/m2 | 26.4 (3.7) | 27.5 (5.5) | 0.28 |
| Feeding type | |||
| Exclusively formula fed at visit 1, n (%) | 5 (19.2) | 11 (11.3) | 0.29 |
| Exclusively formula fed at visit 2, n (%) | 18 (69.2) | 24 (30.8) | <0.0001 |
Data expressed as mean (standard deviation) for continuous variables or n (%) for categorical variables. BMI = body mass index.
*
Student t tests used to compare continuous variables and χ2 or Fisher exact test used to compare categorical variables.
†
Energy deficit calculated by using a 120 kcal · kg−1 · day−1 goal and subtracting or adding the actual amount of energy received.
‡
Protein deficit calculated by using a goal of 3.5 g · kg−1 · day−1 and subtracting or adding the actual amount of grams received.
§
Values ranged from 17.83 to 230.56.
‖
Values ranged from −2.59 to 5.93.
¶
Values ranged from 2 to 35.