title: Concentrations of retinoids in early pregnancy and in newborns and their mothers.
abstract: BACKGROUND
  Retinoids are vital for embryonic development; both excesses and deficiencies of vitamin A are known to give similar patterns of birth defects. Concentrations of retinol in newborns and in pregnant women have been investigated, but concentrations of the biologically active metabolite all-trans retinoic acid and its isomer 13-cis retinoic acid have not.
  
  
  OBJECTIVE
  We measured serum concentrations of these retinoid derivatives in newborns and their mothers and in women in the first trimester of pregnancy, when embryonic differentiation (organogenesis) takes place.
  
  
  METHODS
  In this descriptive study, 10 newborns from normal deliveries and their mothers and 16 healthy women in their first trimester of pregnancy were studied. Seventeen healthy women served as control subjects. all-trans and 13-cis Retinoic acid and retinol concentrations were measured by HPLC.
  
  
  RESULTS
  The newborns had significantly lower retinol concentrations (1.0 micromol/L) than did their mothers (1.7 micromol/L; P = 0.013). Serum all-trans retinoic acid was also significantly lower in the newborns (3.4 nmol/L) than in their mothers (5.8 nmol/L; P = 0.008). In addition, serum concentrations of 13-cis retinoic acid were significantly lower in the newborns (2.0 nmol/L) than in their mothers (2.6 nmol/L; P = 0.005). The serum concentrations of all-trans retinoic acid and retinol did not correlate in any group.
  
  
  CONCLUSIONS
  Retinol concentrations do not accurately reflect the concentrations of the biologically active derivative all-trans retinoic acid.
authors.affiliation: Institute of Laboratory Medicine, Department of Clinical Chemistry, Lund University, Lund, Sweden. maria.berggren_soderlund@klinkem.lu.se
authors.forename: Maria
authors.initials: M
authors.lastname: Berggren Söderlund
authors.forename: Göran A
authors.initials: GA
authors.lastname: Fex
authors.forename: Peter
authors.initials: P
authors.lastname: Nilsson-Ehle
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D007231:Infant, Newborn / Q000097:blood*; D007536:Isomerism; D015474:Isotretinoin / Q000097:blood; D008431:Maternal-Fetal Exchange; D008875:Middle Aged; D009035:Mothers; D011247:Pregnancy / Q000097:blood*; D011261:Pregnancy Trimester, First / Q000097:blood; D012176:Retinoids / Q000097:blood*; D014212:Tretinoin / Q000097:blood
chemical_list: D012176:Retinoids; D014212:Tretinoin; D015474:Isotretinoin