title: Low vitamin B12 intake during pregnancy and lactation and low breastmilk vitamin 12 content in rural Kenyan women consuming predominantly maize diets.
abstract: BACKGROUND
  Vitamin B12 deficiency during pregnancy and lactation may negatively affect fetal growth, brain development, pregnancy outcome, and breastmilk vitamin B12 content.
  
  
  OBJECTIVE
  To examine associations between pregnant and lactating women's vitamin B12 intake and pregnancy outcomes, breastmilk vitamin B12 concentration, and growth and development of breastfed infants from birth to 6 months.
  
  
  METHODS
  One hundred thirty-eight Kenyan women were followed during pregnancy, with 98 followed through 6 months of lactation and providing 294 randomly collected breastmilk samples. Maternal hematologic analyses were performed for erythrocyte morphology, erythrocyte size, and serum vitamin B12 concentration. Women's and infants'food intake was assessed. Breastmilk vitamin B12 was measured by a competitive binding isotope dilution technique. Infant anthropometric data and the Brazelton Neonatal Behavioral Assessment Scale (BNBAS) were assessed within 3 days after birth. The Infant Bayley Motor Scale was assessed at 6 months. Statistical analyses included simple regression and correlation analyses in relation to vitamin B12 status and gestational age.
  
  
  RESULTS
  Intrauterine growth restriction and stillbirths were correlated with maternal macrocytic anemia and hypersegmented polymorphonuclear nuclei. Postpartum maternal vitamin B12 intake influenced breastmilk vitamin B12 levels 1 to 6 months postpartum. No associations were found between vitamin B12 intake during pregnancy or vitamin B12 levels in breastmilk and infant length, weight, or head circumference at birth or 6 months. Vitamin B12 intake during pregnancy was correlated with improved scores on infants' BNBAS reflex subscale (R = -0.19, p = .05) with adjustment for gestational age. Bayley Motor Scale results at 6 months were not significantly associated with breastmilk or supplemental feeding vitamin B12 content.
  
  
  CONCLUSIONS
  Vitamin B12 deficiency may adversely affect pregnancy outcome, infant reflexes at birth, and breastmilk vitamin B12 content.
authors: Department of Community Health Sciences, UCLA Fielding School of Public Health, P.O. Box 951772, Los Angeles, CA 90095, USA. cneumann@ucla.edu
authors: Charlotte G
authors: CG
authors: Neumann
authors: Susan M
authors: SM
authors: Oace
authors: M Pia
authors: MP
authors: Chaparro
authors: Dena
authors: D
authors: Herman
authors: Natalie
authors: N
authors: Drorbaugh
authors: Nimrod O
authors: NO
authors: Bwibo
mesh_terms: D000328:Adult; D000886:Anthropometry; D004032:Diet; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007630:Kenya / Q000453:epidemiology; D007774:Lactation; D008895:Milk, Human / Q000737:chemistry*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood; D011256:Pregnancy Outcome; D012424:Rural Population; D050497:Stillbirth / Q000453:epidemiology; D014805:Vitamin B 12 / Q000008:administration & dosage* / Q000032:analysis / Q000097:blood; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000150:complications*; D003313:Zea mays
chemical_list: D014805:Vitamin B 12