title: Maternal vitamin D₃ supplementation at 50 μg/d protects against low serum 25-hydroxyvitamin D in infants at 8 wk of age: a randomized controlled trial of 3 doses of vitamin D beginning in gestation and continued in lactation.
abstract: BACKGROUND
  Vitamin D supplementation is recommended for breastfed infants. Maternal supplementation beginning in gestation is a potential alternative, but its efficacy in maintaining infant 25-hydroxyvitamin D [25(OH)D] concentration after birth is unknown.
  
  
  OBJECTIVE
  We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs (>30, >40, >50, and >75 nmol/L) by dose at 8 wk of age.
  
  
  METHODS
  Pregnant women (n = 226) were randomly allocated to receive 10, 25, or 50 μg vitamin D₃/d from 13 to 24 wk of gestation until 8 wk postpartum, with no infant supplementation. Mother and infant blood was collected at 8 wk postpartum.
  
  
  RESULTS
  At 8 wk postpartum, mean [nmol/L (95% CI)] infant 25(OH)D at 8 wk was higher in the 50-μg/d [75 (67, 83)] than in the 25-μg/d [52 (45, 58)] or 10-μg/d [45 (38, 52)] vitamin D groups (P < 0.05). Fewer infants born to mothers in the 50-μg/d group had a 25(OH)D concentration <30 nmol/L (indicative of deficiency) than infants in the 25- and 10-μg/d groups, respectively (2% compared with 16% and 43%; P < 0.05). Fewer than 15% of infants in the 10- or 25-μg/d groups achieved a 25(OH)D concentration >75 nmol/L compared with 44% in the 50-μg/d group (P < 0.05). Almost all infants (∼98%, n = 44) born to mothers in the 50-μg/d group achieved a 25(OH)D concentration >30 nmol/L. At 8 wk postpartum, mean maternal 25(OH)D concentration was higher in the 50-μg/d [88 (84, 91)] than in the 25-μg/d [78 (74, 81)] or 10-μg/d [69 (66, 73)] groups (P < 0.05).
  
  
  CONCLUSIONS
  Maternal supplementation beginning in gestation with 50 μg vitamin D₃/d protects 98% of unsupplemented breastfed infants against 25(OH)D deficiency (<30 nmol/L) to at least 8 wk, whereas 10 or 25 μg vitamin D/d protects only 57% and 84% of infants, respectively.
authors.affiliation: Food, Nutrition and Health.
authors.forename: Kaitlin M
authors.initials: KM
authors.lastname: March
authors.affiliation: Food, Nutrition and Health.
authors.forename: Nancy N
authors.initials: NN
authors.lastname: Chen
authors.affiliation: Food, Nutrition and Health.
authors.forename: Crystal D
authors.initials: CD
authors.lastname: Karakochuk
authors.affiliation: Clinical and Population Perinatal Health Research, Kolling Institute, University of Sydney, Sydney, Australia;
authors.forename: Antonia W
authors.initials: AW
authors.lastname: Shand
authors.affiliation: Department of Paediatrics, and.
authors.forename: Sheila M
authors.initials: SM
authors.lastname: Innis
authors.affiliation: Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada;
authors.forename: Peter
authors.initials: P
authors.lastname: von Dadelszen
authors.affiliation: Food, Nutrition and Health.
authors.forename: Susan I
authors.initials: SI
authors.lastname: Barr
authors.affiliation: Canadian Center for Functional Medicine, Coquitlam, Canada;
authors.forename: Michael R
authors.initials: MR
authors.lastname: Lyon
authors.affiliation: College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada; and.
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Whiting
authors.affiliation: School of Dietetics and Human Nutrition, McGill University, Montréal, Canada.
authors.forename: Hope A
authors.initials: HA
authors.lastname: Weiler
authors.affiliation: Food, Nutrition and Health, tim.green@ubc.ca.
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Green
mesh_terms: D000328:Adult; D001955:British Columbia / Q000453:epidemiology; D002112:Calcifediol / Q000097:blood* / Q000378:metabolism; D002118:Calcium / Q000097:blood; D002657:Child Development; D002762:Cholecalciferol / Q000008:administration & dosage* / Q000009:adverse effects / Q000172:deficiency / Q000627:therapeutic use; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D006934:Hypercalcemia / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D007231:Infant, Newborn; D057194:Intention to Treat Analysis; D007774:Lactation / Q000378:metabolism; D008297:Male; D039382:Maternal Nutritional Physiological Phenomena; D010349:Patient Compliance; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D015995:Prevalence; D014808:Vitamin D Deficiency / Q000097:blood / Q000151:congenital / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D002762:Cholecalciferol; D002112:Calcifediol; D002118:Calcium
keywords: 25(OH)D; infant; lactation; postpartum; pregnancy; supplement; vitamin D