Table 1 Demographic characteristics and outcomes over time
From: A retrospective cohort study of factors relating to the longitudinal change in birth weight
Variable | 1995–1997 (n = 9447) | 1998–2000 (n = 8801) | 2001–2003 (n = 8399) | 2004–2006 (n = 8418) | 2007–2010 (n = 8182) | Total Change Over time | P value* |
|---|---|---|---|---|---|---|---|
Maternal Age (years) | 25.1 (6.2) | 25.5 (6.2) | 25.8 (6.3) | 25.8 (6.2) | 25.6 (6.2) | 0.5 | <0.001 |
Nulliparity (%) | 39.4 % | 36.5 % | 37.8 % | 38.6 % | 38.8 % | −0.6 % | 0.684 |
Smoking (%) | 20.4 % | 22.2 % | 19.0 % | 21.2 % | 20.2 % | −0.2 % | 0.383 |
Cesarean (%) | 16.1 % | 16.0 % | 20.1 % | 23.0 % | 22.9 % | 6.8 % | <0.001 |
BMI (kg/m2) | 30.9 (6.6) | 31.6 (6.7) | 31.9 (6.9) | 32.4 (7.2) | 32.7 (7.3) | 1.8 | <0.001 |
Hypertension (%) | 2.4 % | 2.9 % | 2.8 % | 4.2 % | 4.7 % | 2.3 % | <0.001 |
Diabetes (%) | 3.2 % | 4.4 % | 5.2 % | 5.3 % | 4.8 % | 1.6 % | <0.001 |
%African American | 37.2 % | 38.3 % | 38.1 % | 42.1 % | 45.4 % | 8.2 % | <0.001 |
Mean BW (g) | 3325 (483) | 3324 (481) | 3307 (475) | 3295 (467) | 3253 (457) | −72 | <0.001 |
Median BW (g) | 3310 [3010–3635] | 3305 [3005–3630] | 3295 [3995–3605] | 3280 [2995–3590] | 3240 [2955–3545] | −70 | <0.0001 |
Infant Sex (%Male) | 51.1 % | 50.8 % | 50.0 % | 50.7 % | 50.3 % | −0.8 % | 0.283 |
Gestational Age (weeks) | 39.6 (1.3) | 39.5 (1.3) | 39.4 (1.3) | 39.3 (1.2) | 39.2 (1.2) | −0.4 | <0.001 |
Mean BL (cm) | 50.4 (2.5) | 50.1 (2.5) | 50.0 (2.6) | 49.6 (2.6) | 49.4 (2.5) | −1.0 | <0.001 |
Mean PI (kg/m3) | 2.61 (0.33) | 2.64 (0.32) | 2.66 (0.34) | 2.71 (0.36) | 2.71 (0.35) | 0.10 | <0.001 |