Table 2.
Comparison of selected demographic and clinical variables between the infants born with extremely low birth weight (ELBW children) and infants born at term (control children)
| Demographic and clinical variables | Control (full term) group (n = 36) | Study (ELBW) group (n = 64) | p valuea |
|---|---|---|---|
| Demographic variables | |||
| Female | 17 (47 %) | 43 (67 %) | 0.06b |
| Birth weight (g) | 3570 (3395–3880) | 875 (750–960) | <0.01c |
| Gestational age (weeks)) | 40 (39–40) | 27 (25–28) | <0.01c |
| Vaginal delivery | 31 (86 %) | 13 (20 %) | <0.01b |
| Multiple pregnancy | 0 | 9 (14 %) | 0.024b |
| Small for gestational age | 2 (6 %) | 19 (30 %) | 0.004b |
| First follow-up (at age 7 years) | |||
| Age at evaluation (years); median (25th-75th percentile) | 6.9 (6.4–7.4) | 6.5 (6.4–6.8) | 0.04c |
| Height (cm) | 124 ± 7.4 | 116 ± 6.3 | <0.01d |
| Height (z score) | 0.21 ± 1.0 | −1.08 ± 1.3 | <0.01d |
| Weight (kg) | 25.2 ± 5.3 | 19.5 ± 3.8 | <0.01d |
| Weight (z score) | 0.26 ± 1.2 | −0.92 ± 1.3 | <0.01d |
| Second follow-up (at age 11 years) | |||
| Age at evaluation (years) | 10.7 (10.2–11.1) | 11 (10.8–11.3) | 0.01c |
| Height (cm) | 146 ± 8 | 141 ± 8 | <0.01d |
| Height (z score) | 0.20 ± 1.1 | −0.88 ± 1.2 | <0.01d |
| Weight (kg) | 40.4 ± 9.9 | 33.7 ± 8.2 | <0.01d |
| Weight (z score | 0.24 ± 1.2 | −0.92 ± 1.3 | <0.01d |
Data are presented as the number of patients with the percentage given in parenthesis, the median with the IQR given in parenthesis and the mean ± standard deviation (SD), as appropriate
aStatistical significance was defined at the p = 0.05 level for the two-sided test
b p value using the Fisher exact test
c p value using the Mann–Whitney U test
d p value using Student’s t test