title: Folic acid, Vitamin B(12), and homocysteine in smoking and non-smoking pregnant women.
abstract: BACKGROUND
  Lower plasma levels of vitamins may result in hyperhomocysteinemia, a known risk factor in pregnancy. As smoking may alter nutrition, we were interested in its effect on folate and Vitamin B(12) in pregnancy.
  
  
  METHODS
  A cross-sectional study of 62 smoking and 76 non-smoking healthy pregnant women. Serum folic acid, Vitamin B(12) and homocysteine were measured at four points in pregnancy: 0-10, 11-20, 21-30 and 31-40 weeks.
  
  
  RESULTS
  Folate concentrations of the smoking women decreased continuously during pregnancy, and were significantly lower than those of non-smoking women during the last 30 weeks. Vitamin B(12) levels decreased significantly in both groups. The homocysteine levels were higher in the smoking group during the second-half of pregnancy.
  
  
  CONCLUSIONS
  Smoking women have lower and decreasing folate levels during pregnancy, possibly as a result of lower intake of these nutrients. Lower folate levels can lead to hyperhomocysteinemia, a known risk factor for several complications in pregnancy. This is an other important reason to convince pregnant women to refrain from smoking.
authors.affiliation: Department of Haematology, Atrium Medical Centre, P.O. Box 4446, 6401 CX Heerlen, The Netherlands.
authors.forename: J W J
authors.initials: JW
authors.lastname: van Wersch
authors.forename: Y
authors.initials: Y
authors.lastname: Janssens
authors.forename: J A
authors.initials: JA
authors.lastname: Zandvoort
mesh_terms: D003430:Cross-Sectional Studies; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005865:Gestational Age; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000150:complications; D009752:Nutritional Status; D011247:Pregnancy; D011248:Pregnancy Complications; D012016:Reference Values; D012907:Smoking / Q000097:blood*; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D006710:Homocysteine; D005492:Folic Acid; D014805:Vitamin B 12