Table 1.
Maternal Characteristics by Maternal Use of Supplements From 4 Weeks Before to 8 Weeks After Conception Among 94 228 Births Without Chromosomal Aberrations in the DNBC, Denmark, 1996–2003
| Characteristics | TotalN=94 228 (100%) | No Supplementsn=31 322 (33.2%) | Other Supplements No Folic Acidn=3453 (3.7%) | Folic Acid Onlyn=3889 (4.1%) | Folic Acid Plus Other Supplementsn=55 564 (59.0%) | P Value, No Folic Acid vs Folic Acid Usea |
|---|---|---|---|---|---|---|
| Year of birthb | ||||||
| 1996 | 139 (0.15) | 69 (49.6) | 12 (8.6) | 0 (0) | 58 (41.7) | <0.0001 |
| 1997 | 750 (0.80) | 346 (46.1) | 43 (5.7) | 9 (1.2) | 352 (46.9) | |
| 1998 | 12 077 (12.8) | 4442 (36.8) | 767 (6.4) | 260 (2.2) | 6608 (54.7) | |
| 1999 | 18 548 (19.7) | 7188 (38.8) | 924 (5.0) | 459 (2.5) | 9977 (53.8) | |
| 2000 | 20 540 (21.8) | 7230 (35.2) | 764 (3.7) | 823 (4.0) | 11 723 (57.1) | |
| 2001 | 20 135 (21.4) | 6254 (31.1) | 555 (2.8) | 933 (4.6) | 12 393 (61.6) | |
| 2002 | 18 084 (19.2) | 4681 (25.9) | 324 (1.8) | 1123 (6.2) | 11 956 (66.1) | |
| 2003 | 3955 (4.2) | 1112 (28.1) | 64 (1.6) | 282 (7.1) | 2497 (63.1) | |
| Maternal age, yb | ||||||
| ≤24 | 8996 (9.55) | 3871 (43.0) | 343 (3.8) | 287 (3.2) | 4495 (50.0) | <0.0001 |
| 25–29 | 35 891 (38.1) | 11 515 (32.1) | 1187 (3.3) | 1488 (4.2) | 21 701 (60.5) | |
| 30–34 | 35 117 (37.3) | 11 277 (32.1) | 1279 (3.6) | 1479 (4.2) | 21 082 (60.0) | |
| ≥35 | 14 113 (15.0) | 4628 (32.8) | 640 (4.5) | 627 (4.4) | 8218 (58.2) | |
| Missing | 111 (0.12) | 31 (27.9) | 4 (3.6) | 8 (7.2) | 68 (61.3) | |
| Birth order | ||||||
| First | 41 698 (44.3) | 12 255 (29.4) | 1374 (3.3) | 2049 (4.9) | 26 020 (62.4) | <0.0001 |
| Second | 32 425 (34.4) | 10 829 (33.4) | 1226 (3.8) | 1188 (3.7) | 19 182 (59.2) | |
| Third | 11 435 (12.1) | 4542 (39.7) | 497 (4.4) | 384 (3.4) | 6012 (52.6) | |
| Fourth or higher | 2649 (2.8) | 1171 (44.2) | 146 (5.5) | 76 (2.9) | 1256 (47.4) | |
| Missing | 6021 (6.4) | 2525 (41.9) | 210 (3.5) | 192 (3.2) | 3094 (51.4) | |
| Maternal body mass index before pregnancy (kg/m2)b | ||||||
| Single | 90 180 (95.7) | 30 261 (33.6) | 3318 (3.7) | 3716 (4.1) | 52 885 (58.6) | <0.0001 |
| Twins/triplets | 4048 (4.3) | 1061 (26.2) | 135 (3.3) | 173 (4.3) | 2679 (66.2) | |
Data are shown as n (%). DNBC indicates Danish National Birth Cohort.
a
No folic acid use (no/other supplements, no folic acid) vs folic acid use (folic acid only/folic acid plus other supplements) 4 weeks before to 8 weeks after gestation (combining −4 to 0, 0–4, and 5–8 weeks).
b
Data from Medical Birth Registry.