Table 1.
Associations between child and parental characteristics and tertiles of Z-score weight gain for length gain rate in the first 3 postnatal months.
| Tertiles of weight gain rate for length gain rate in the first 3 months after birth | ||||
|---|---|---|---|---|
| 1st Z-score WLG tertile (mean : −1.1) | 2nd Z-score WLG tertile (mean : −0.049) | 3rd Z-score WLG tertile (mean : 1.1) | ||
| N = 105 | N = 106 | N = 105 | P value | |
| Child characteristics | ||||
| Infancy | ||||
| Gender (% boys) | 53 | 45 | 48 | 0.49a |
| Gestational age (days)# | 282 (275–288) | 279 (271–286) | 281 (274–286) | 0.07c |
| Birth weight (grams) | 3564 ± 46 | 3430 ± 46 | 3642 ± 46 | 0.005b |
| Birth length (cm) | 50.7 ± 0.22 | 50.7 ± 0.22 | 51.9 ± 0.22 | <0.001b |
| Z-score birth size (SD) | 0.18 ± 0.097 | −0.14 ± 0.096 | −0.044 ± 0.097 | 0.056b |
| Mean weight gain (g/day) | 24.6 ± 0.26 | 28.0 ± 0.26 | 32.1 ± 0.26 | <0.001b |
| Mean length gain (mm/day) | 1.1 ± 0.005 | 1.1 ± 0.005 | 1.1 ± 0.005 | 0.95b |
| Breastfeeding (% ever) | 79 | 79 | 80 | 0.98a |
| Exclusive breastfeeding (days)#∗ | 66 (26–127) | 72 (28–136) | 79 (40–145) | 0.26c |
| Childhood | ||||
| Age at 5 years visit (years)# | 5.4 (5.2–5.5) | 5.3 (5.2–5.4) | 5.3 (5.2–5.4) | 0.16c |
| Weight (kg) | 19.4 ± 0.26 | 19.8 ± 0.26 | 21.6 ± 0.26 | <0.001b |
| Height (cm) | 114.2 ± 0.45 | 114.3 ± 0.45 | 116.7 ± 0.45 | <0.001b |
| BMI (kg/m2)# | 14.8 (14.0–15.4) | 14.9 (14.0–16.1) | 15.6 (14.8–16.6) | <0.001c |
| Waist circumference (mm)# | 52.2 (50.2–53.9) | 52.0 (49.9–54.1) | 54.0 (51.5–56.3) | <0.001c |
| Systolic blood pressure (mmHg) | 105 ± 0.75 | 105 ± 0.76 | 106 ± 0.76 | 0.46b |
| Diastolic blood pressure (mmHg) | 55 ± 0.68 | 56 ± 0.68 | 55 ± 0.68 | 0.60b |
|
| ||||
| Parental characteristics | ||||
| Maternal age at childbirth (years) | 32.5 ± 0.34 | 32.4 ± 0.34 | 32.1 ± 0.34 | 0.70b |
| Maternal BMI (kg/m2) | 25.4 ± 0.44 | 24.8 ± 0.44 | 24.9 ± 0.43 | 0.58b |
| Paternal BMI (kg/m2) | 25.6 ± 0.34 | 25.6 ± 0.32 | 25.6 ± 0.34 | 0.99b |
| Maternal gestational diabetes (%) | 0 | 0 | 3 | 0.11d |
| Maternal smoking-prenatal (%) | 6 | 6 | 1 | 0.13a |
| Parental smoking-postnatal (%) | 0.039a | |||
| Neither one of the parents | 62 | 70 | 79 | |
| One parent | 31 | 20 | 19 | |
| Both parents | 7 | 10 | 2 | |
| Socio economic status (% high educated) | 79 | 76 | 69 | 0.26a |
| Maternal ethnicity (% western) | 93 | 91 | 92 | 0.85a |
Values are means with standard errors in case of continuous variables and percentages in case of frequencies. In case of skewed data (#), medians with interquartile range were presented.
#Not normally distributed.
*Within those ever breastfed.
aChi-square test.
bANOVA.
cKruskall Wallis test.
dFisher's exact test.