Table 1.
Concentrations of plasma folate, vitamin B6, vitamin B12 and homocysteine according to maternal characteristics (n=913)
| n (%) | Folate, nmol/L | P | B6, nmol/L | P | B12, pmol/L | P | Hcy, µmol/L | P | |
|---|---|---|---|---|---|---|---|---|---|
| Age | |||||||||
| <35 years | 705 (77.2) | 33.8 (21.8, 43.7) | 0.001 | 57.9 (25.1, 109.7) | 0.106 | 208 (165, 258) | 0.987 | 4.8 (4.2, 5.6) | 0.940 |
| ≥35 years | 208 (22.8) | 37.1 (30.1, 47.7) | 71.2 (29.0, 121.4) | 211 (168, 253) | 4.9 (4.2, 5.6) | ||||
| Ethnicity | |||||||||
| Chinese | 498 (54.5) | 35.8 (27.8, 47.1)a | 0.001 | 63.0 (29.2, 115.6)a | 0.026 | 219 (176, 259)a | 0.001 | 4.8 (4.2, 5.4)a | 0.001 |
| Malay | 250 (27.4) | 29.3 (16.0, 40.3)a,b | 52.8 (23.1, 102.3)a | 212 (168, 266) b | 5.0 (4.3, 5.9)a | ||||
| Indian | 165 (18.1) | 35.7 (24.0, 44.7)b | 64.5 (25.4, 109.5) | 186 (142, 226)a,b | 4.9 (4.2, 5.6) | ||||
| Education | |||||||||
| None/Primary/ Secondary | 279 (30.6) | 32.5 (19.3, 40.4)a,b | 0.001 | 62.3 (24.5, 114.5) | 0.701 | 204 (166, 258) | 0.256 | 4.9 (4.3, 5.7) | 0.120 |
| Post-secondary | 318 (34.8) | 33.7 (24.1, 44.0)a,c | 63.3 (28.4, 114.7) | 208 (162, 252) | 4.9 (4.2, 5.6) | ||||
| University | 316 (34.6) | 37.7 (28.1, 48.9)b,c | 56.5 (27.0, 107.1) | 218 (170, 261) | 4.7 (4.2, 5.4) | ||||
| Monthly household income (SGD) | |||||||||
| <1999 | 127 (13.9) | 31.8 (18.3, 44.2)a | 0.001 | 50.2 (23.3, 113.0) | 0.198 | 209 (174, 249) | 0.376 | 4.9 (4.2, 5.8) | 0.339 |
| 2000-5999 | 543 (59.5) | 33.8 (23.5, 42.5)b | 67.9 (27.8, 113.6) | 206 (162, 258) | 4.8 (4.2, 5.6) | ||||
| ≥6000 | 243 (26.6) | 37.9 (30.0, 51.1)a,b | 52.6 (26.1, 108.2) | 215 (175, 263) | 4.8 (4.2, 5.4) | ||||
| Pre-pregnancy BMI (kg/m2) | |||||||||
| Under (<18.5) | 110 (12.1) | 34.6 (24.4, 44.1) | 0.204 | 55.1 (24.9, 109.4) | 0.625 | 230 (176, 285)a,b | 0.001 | 4.9 (4.1, 5.6) | 0.541 |
| Normal (18.5-22.9) | 457 (50.1) | 35.3 (25.0, 45.9) | 60.8 (26.1, 114.9) | 220 (175, 273)c,d | 4.8 (4.2, 5.5) | ||||
| Over (23.0-27.5) | 215 (23.5) | 33.7 (24.1, 44.3) | 67.1 (27.8, 109.3) | 200 (158, 245)a,c | 4.8 (4.3, 5.6) | ||||
| Obese (>27.5) | 131 (14.3) | 32.2 (20.8, 42.6) | 58.5 (21.5, 116.4) | 187 (139, 226)b,d | 5.0 (4.2, 5.7) | ||||
| Smoking during pregnancy | |||||||||
| Non-smoker | 788 (86.3) | 35.0 (25.4, 45.0)a | 0.001 | 62.7 (27.0, 113.4) | 0.253 | 214 (168, 258) | 0.061 | 4.8 (4.2, 5.5) | 0.364 |
| Former smoker | 101 (11.1) | 26.2 (14.0, 38.5)a | 52.8 (23.3, 104.7) | 192 (163, 235) | 4.8 (4.0, 5.7) | ||||
| Current smoker | 24 (2.6) | 36.3 (21.6, 44.8) | 89.3 (35.0, 105.1) | 194 (173, 286) | 5.2 (4.4, 6.0) | ||||
| Exercise (MET.mins/week) | |||||||||
| Low (<600) | 291 (31.9) | 34.3 (25.0, 43.8) | 0.060 | 61.8 (28.7, 108.2) | 0.814 | 218 (175, 256) | 0.148 | 4.8 (4.2, 5.5) | 0.793 |
| Moderate (600-1500) | 278 (30.4) | 35.3 (24.7, 46.9) | 66.9 (27.0, 113.1) | 215 (168, 264) | 4.8 (4.3, 5.5) | ||||
| High (>1500) | 344 (37.7) | 33.5 (22.9, 43.0) | 56.9 (24.6, 116.0) | 202 (162, 252) | 4.9 (4.2, 5.7) | ||||
| Alcohol consumption | |||||||||
| No | 894 (97.9) | 34.5 (24.5, 44.6) | 0.210 | 61.8 (26.3, 113.0) | 0.115 | 209 (165, 256) | 0.104 | 4.8 (4.2, 5.6) | 0.445 |
| Yes | 19 (2.1) | 32.6 (18.8, 38.5) | 33.9 (18.8, 93.2) | 250 (187, 281) | 5.1 (3.7, 6.2) | ||||
| Parity | |||||||||
| Nulliparous | 388 (42.5) | 34.7 (24.5, 44.9) | 0.420 | 63.6 (27.8, 113.0) | 0.396 | 220 (177, 264) | 0.005 | 4.8 (4.2, 5.5) | 0.659 |
| Multiparous | 525 (57.5) | 34.1 (24.1, 44.1) | 57.2 (24.7, 111.5) | 203 (162, 252) | 4.8 (4.2, 5.6) | ||||
| Family history of diabetes | |||||||||
| No | 642 (70.3) | 34.8 (24.4, 44.9) | 0.618 | 62.9 (26.1, 113.6) | 0.482 | 215 (169, 266) | 0.001 | 4.8 (4.2, 5.6) | 0.939 |
| Yes | 271(29.7) | 33.6 (24.4, 43.5) | 55.0 (25.0, 106.5) | 197 (159, 245) | 4.9 (4.3, 5.5) | ||||
| Previous GDM | |||||||||
| No | 878 (96.2) | 34.5 (24.1, 44.5) | 0.742 | 60.8 (25.9, 113.0) | 0.300 | 209 (166, 258) | 0.533 | 4.8 (4.2, 5.6) | 0.434 |
| Yes | 35 (3.8) | 34.5 (24.8, 41.4) | 40.7 (21.8, 85.0) | 205 (158, 252) | 4.7 (4.2, 5.3) | ||||
Values are medians (IQRs) or n (%). P-values are for Wilcoxon rank-sum or Kruskal-Wallis tests of differences between groups (a, b, c, d groups with the same superscript symbols have significantly different concentrations). Hcy, homocysteine.
Imputed missing values: n=12 education, n=12 monthly household income, n=57 pre-pregnancy BMI, n=3 smoking status, n=1 alcohol consumption, n=1 parity, n=23 family history of diabetes, n=23 previous GDM