Table 1.
Maternal characteristics according to maternal use of supplements in week 13 to 17 of pregnancy and median folate in plasma from week 18 (25th and 75th percentile in parenthesis), N=2911.
| No supp | Other supp | Folic acid only | Folic acid plus | Plasma folate | P values | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | n | % | nmol/L | 25th and 75th | ||||
| Maternal education | |||||||||||||
| <12 | 334 | (29.8) | 127 | (20.0) | 42 | (19.9) | 159 | (16.8) | 7.1 | (5.1-11.5) | <0.000a) | ||
| 12 | 196 | (17.5) | 90 | (14.2) | 19 | (9.0) | 137 | (14.5) | 7.9 | (5.2-12.9) | |||
| 13-16 | 405 | (36.2) | 264 | (41.6) | 97 | (46.0) | 418 | (44.1) | 9.3 | (6.3-16.0) | |||
| 17+ | 148 | (13.2) | 132 | (20.8) | 45 | (21.3) | 215 | (22.7) | 10.4 | (7.2-17.6) | |||
| missing | 36 | (3.2) | 21 | (3.3) | 8 | (3.8) | 18 | (1.9) | 8.1 | (5.8-12.3) | |||
|
| |||||||||||||
| Maternal age | |||||||||||||
| <25 | 168 | (15.0) | 83 | (13.1) | 19 | (9.0) | 95 | (10.0) | 6.7 | (4.8-10.0) | <0.000 a) | ||
| 25-29 | 403 | (36.0) | 206 | (32.5) | 75 | (35.5) | 311 | (32.8) | 8.2 | (5.9-14.1) | |||
| 30-34 | 368 | (32.9) | 253 | (39.9) | 89 | (42.2) | 396 | (41.8) | 9.8 | (6.4-16.3) | |||
| 35+ | 180 | (16.1) | 92 | (14.5) | 28 | (13.3) | 145 | (15.3) | 9.9 | (6.1-16.4) | |||
|
| |||||||||||||
| Pregnancy planning | |||||||||||||
| No | 260 | (23.2) | 125 | (19.7) | 32 | (15.2) | 185 | (19.5) | 7.7 | (5.3-11.7) | <0.000 a) | ||
| Yes | 838 | (74.9) | 496 | (78.2) | 177 | (83.9) | 747 | (78.9) | 9.1 | (6.1-15.6) | |||
| missing | 21 | (1.9) | 13 | (2.1) | 2 | (0.9) | 15 | (1.6) | 9.1 | (6.4-16.0) | |||
|
| |||||||||||||
| Maternal BMI | |||||||||||||
| <25 | 680 | (60.8) | 435 | (68.6) | 141 | (66.8) | 652 | (68.8) | 9.2 | (6.3-15.9) | <0.000 a) | ||
| 25-29 | 239 | (21.4) | 133 | (21.0) | 42 | (19.9) | 172 | (18.2) | 8.0 | (5.6-12.8) | |||
| 30-34 | 96 | (8.6) | 35 | (5.5) | 16 | (7.6) | 66 | (7.0) | 7.3 | (5.0-12.2) | |||
| 35+ | 42 | (3.8) | 13 | (2.1) | 7 | (3.3) | 28 | (3.0) | 7.2 | (5.0-12.0) | |||
| missing | 62 | (5.5) | 18 | (2.8) | 5 | (2.4) | 29 | (3.1) | 7.6 | (5.3-11.5) | |||
|
| |||||||||||||
| Parity | |||||||||||||
| 0 | 395 | (34.7) | 285 | (44.5) | 87 | (41.0) | 457 | (48.1) | 9.8 | (6.4-16.8) | <0.000 a) | ||
| 1 | 448 | (39.4) | 232 | (36.3) | 88 | (41.5) | 330 | (34.7) | 8.6 | (6.0-14.0) | |||
| 2+ | 294 | (25.9) | 123 | (19.2) | 37 | (17.5) | 163 | (17.2) | 7.6 | (5.2-12.7) | |||
|
| |||||||||||||
| Maternal smoking | |||||||||||||
| No | 923 | (82.5) | 557 | (87.9) | 195 | (92.4) | 836 | (88.3) | 9.1 | (6.1-15.5) | <0.000 a) | ||
| Sometimes | 52 | (4.6) | 29 | (4.6) | 4 | (1.9) | 39 | (4.1) | 7.4 | (5.0-13.1) | |||
| Daily | 127 | (11.3) | 43 | (6.8) | 12 | (5.7) | 65 | (6.9) | 6.5 | (4.3-9.8) | |||
| missing | 17 | (1.5) | 5 | (0.8) | 0 | (0.0) | 7 | (0.7) | 7.3 | (5.5-13.7) | |||
a)
Kruskal-Wallis test used for differences in plasma medians.