Table 1.
Maternal characteristics, supplement use and circulating B vitamin concentrations according to pregnancy risk classification at 18–20 weeks gestation
| Demographics | Total cohort | Pregnancy groups | P value | |
|---|---|---|---|---|
| Low risk | High risk | |||
| n | 137 | 46 | 91 | |
| Age (years) | 33.0 (31.8–34.2) | 31.1 (29.5–32.4) | 34.0 (32.4–35.6) | 0.020 |
| BMI (kg) | 28.5 (27.5–29.7) | 26.5 (25.4–27.8) | 29.5 (28.1–31.1) | 0.010 |
| Smokers | 21 (15.3%) | 3 (6.5%) | 18 (19.8%) | 0.042 |
| Vitamin supplements | ||||
| Folic acid | 110 (80.3%) | 33 (71.7%) | 77 (84.6%) | 0.074 |
| Vitamin B12 | 65 (47.4%) | 21 (45.7%) | 44 (48.4%) | 0.748 |
| Vitamin B6 | 65 (47.4%) | 21 (45.7%) | 44 (48.4%) | 0.748 |
| Dietary intake | ||||
| Folate (µg/day) | 283 (254–311) | 308 (268–327) | 261 (256–297) | 0.526 |
| Blood micronutrients | ||||
| Hcy µmol/L | 4.6 (4.4–4.9) | 4.3 (4.0–4.5) | 4.7 (4.4–5.1) | 0.095 |
| RBC folate nmol/L | 652 (613–692) | 652 (587–718) | 652 (602–702) | 0.994 |
| Serum folate nmol/L | 26.5 (24.9–28.2) | 25.4 (22.9–27.8) | 27.1 (24.9–29.3) | 0.369 |
| Serum B12 pmol/L | 239 (215–265) | 231 (194–269) | 244 (212–276) | 0.555 |
| RBC B6%* | 41.9 (39.1–44.7) | 48.5 (45.5–51.6) | 38.6 (34.8–42.4) | 0.001 |
Values are mean (95% confidence interval) or numbers (percentage) calculated using t‐tests and chi‐squared analyses. BMI, body mass index; RBC, red blood cell. *Based on pyridoxal phosphate activation activity that is inversely related to vitamin B6 concentration. Bold indicates P values that are significant (P < 0.050).