Table 1

Demographic characteristics and serum 25-hydroxyvitamin-D concentrations

CharacteristicsAll infants (n=120)Infants born <28 weeks PMA (n=67)Infants born between 28 and 32 weeks PMA (n=53)
n (%) male51 (43)27 (41)24 (45)
n (%) African–American46 (39)29 (43)17 (32)
PMA in weeks28.1 (1.2)26.4 (1.0)30.4 (0.8)
Birth weight in g1028.1 (236.8)831.5 (231.7)1276.6 (245.9)
Maternal 25(OH)D in nmol/L at delivery49.2 (19.2)44.0 (12.5)55.7 (22.7)*
n (%) mothers with 25(OH)D <50 nmol/L75 (63)45 (67)30 (57)
Infant 25(OH)D in nmol/L at birth46.3 (14.0)42.0 (9.8)51.8 (19.5)**
n (%) infants with 25(OH)D <50 nmol/L76 (64)47 (70)29 (55)**
25(OH)D in nmol/L at 36 weeks PMA or at discharge64 (21.8)59.2 (20.5)71 (23.5)***
n (%) infants with 25(OH)D <50 nmol/L at 36 weeks PMA or at discharge43 (36)27 (40)16 (30)
  • *p=0.02 for difference between 25(OH)D serum concentrations in mothers that delivered at<28 weeks vs 28–32 weeks PMA.

  • **p=0.02 for difference between infants born at <28 weeks vs 28–32 weeks PMA.

  • ***p=0.04 for difference between infants born at 28 weeks vs <28–32 weeks PMA.

  • Values are mean (SD).

  • PMA, postmenstrual age.