At 8 wk postpartum , mean [ nmol/L ( 95 % CI ) ] infant 25 ( OH ) D at 8 wk was higher in the 50-g/d [ 75 ( 67 , 83 ) ] than in the 25-g/d [ 52 ( 45 , 58 ) ] or 10-g/d [ 45 ( 38 , 52 ) ] vitamin D groups ( P < 0.05 ) .