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Table 2 Characteristics of circulating folate, vitamin B12 and homocysteine concentrations in early pregnancy and cord blood

From: Associations of circulating folate, vitamin B12 and homocysteine concentrations in early pregnancy and cord blood with epigenetic gestational age: the Generation R Study

  Early pregnancy Cord blood
Plasma folate concentration, nmol/L 19.8 (6.6, 39.6) 21.2 (11.0, 38.4)
 ≥ 8 nmol/L 1041 (94.5) 1145 (99.9)
 < 8 nmol/L 61 (5.5) 1 (0.1)
Serum total B12 concentration, pmol/L 178.0 (81.9, 428.5) 309.0 (128.0, 869.2)
 ≥ 145 pmol/L 726 (70.1) 1125 (95.7)
 < 145 pmol/L 310 (29.9) 51 (4.3)
Serum active B12 concentrationa, pmol/L 44.0 (21.0, 94.0) 87.0 (39.0, 128.0)
 ≥ 21 pmol/L 757 (97.8) 1124 (99.8)
 < 21 pmol/L 17 (2.2) 2 (0.2)
Plasma homocysteine concentration, μmol/L 7.0 (4.7, 11.5) 9.1 (5.5, 16.4)
 < 19 μmol/L 1082 (99.5) 1090 (99.0)
 ≥ 19 μmol/L 5 (0.5) 11 (1.0)
  1. Values are based on non-imputed data and are median (95% range) for continuous variables and numbers (%) for categorical variables. We calculated standard deviation scores for all exposures to make them more comparable. Overall, 1346 mother–newborn pairs were included in one or more analyses. Not all pairs had information available on all exposure variables in either early pregnancy or cord blood. Missing data: maternal folate (n = 244), maternal total B12 (n = 310), maternal active B12 (n = 572), maternal homocysteine (n = 259), neonatal folate (n = 200), neonatal total B12 (n = 170), neonatal active B12 (n = 220), neonatal homocysteine (n = 245)
  2. aSerum active B12 concentrations were measured in stored serum sampled in early pregnancy and cord blood. As not all participants had enough stored serum available, information on serum active B12 concentrations was available in fewer participants