Table 1. Participant Characteristics.
| Characteristic | Participants, No. (%)a | P Value | |||
|---|---|---|---|---|---|
| Total Group (N = 3205) | Small for Gestational Age (n = 199) | Appropriate for Gestational Age (n = 2714) | Large for Gestational Age (n = 222) | ||
| Maternal pregnancy characteristics | |||||
| Age, mean (SD), yb | 31.1 (4.9) | 30.2 (5.4) | 31.1 (4.8) | 31.9 (4.4) | <.001 |
| Height, mean (SD), cmb | 168.0 (7.3) | 164.5 (6.9) | 168.0 (7.3) | 171.6 (6.9) | <.001 |
| Weight, median (90% range), kgb | 64.0 (50.0-90.0) | 60.0 (47.4-76.7) | 64.0 (50.0-90.0) | 70.0 (57.0-97.0) | <.001 |
| Prepregnancy body mass index, median (90% range)b,c | 22.5 (18.7-32.0) | 22.2 (17.9-29.4) | 22.4 (18.6-32.0) | 24.0 (20.1-32.4) | <.001 |
| Parityd | |||||
| 0 | 1787/3091 (57.8) | 155/197 (78.7) | 1506/2634 (57.2) | 90/212 (42.5) | <.001 |
| ≥1 | 1304/3091 (42.2) | 42/197 (21.3) | 1128/2634 (42.8) | 122/212 (57.5) | |
| Educational leveld | |||||
| Lower | 1400/2954 (47.4) | 102/183 (55.7) | 1199/2514 (47.7) | 86/210 (41.0) | .01 |
| Higher | 1554/2954 (52.6) | 81/183 (44.3) | 1315/2514 (52.3) | 124/210 (59.0) | |
| Folic acid used | |||||
| No | 445/2204 (20.2) | 35/137 (25.5) | 384/1893 (20.3) | 20/142 (14.1) | .06 |
| Yes | 1759/2204 (79.8) | 102/137 (74.5) | 1509/1893 (79.7) | 122/142 (85.9) | |
| Smoking during pregnancyd | |||||
| No | 1968/2550 (77.2) | 101/166 (60.8) | 1695/2176 (77.9) | 137/166 (82.5) | <.001 |
| Yes | 582/2550 (22.8) | 65/166 (39.2) | 481/2176 (22.1) | 29/166 (17.5) | |
| Birth and infant characteristics | |||||
| Boysd | 1573 (49.1) | 100 (50.3) | 1347 (49.6) | 86 (38.7) | .01 |
| Birth weight, mean (SD), gb | 3444 (554) | 2471 (427) | 3436 (439) | 4322 (437) | <.001 |
| Race/ethnicityd | |||||
| European | 2134/3141 (67.9) | 112/194 (57.7) | 1797/2663 (67.5) | 177/219 (80.8) | <.001 |
| Non-European | 1007/3141 (32.1) | 82/194 (42.3) | 866/2663 (32.5) | 42/219 (19.2) | |
| Breastfeeding, everd | 2513/2708 (92.8) | 142/156 (91.0) | 2151/2313 (93.0) | 179/194 (92.3) | .62 |
a
Characteristics are based on observed, not imputed, data.
b
Differences in characteristics for children born small for gestational age, appropriate for gestational age, and large for gestational age were evaluated using 1-way analysis of variance for continuous variables.
c
Calculated as weight in kilograms divided by height in meters squared.
d
Differences in characteristics for children born small for gestational age, appropriate for gestational age, and large for gestational age were evaluated using χ2 test for categorical variables.