title: Bioavailability of iron in two prenatal multivitamin/multimineral supplements.
abstract: OBJECTIVE
  To determine the iron bioavailability in two popular prenatal multivitamin/multimineral supplement tablets containing 27 mg elemental iron.
  
  
  METHODS
  Iron absorption during an eight-hour period following ingestion of a multivitamin/multimineral formulation, both fasting and with a standardized meal, was measured in a group of 30 pregnant women (24-32 weeks of gestation) and statistically compared. The prenatal formulations were Stuartnatal Plus and Materna (Wyeth-Ayerst Pharmaceuticals, Philadelphia, Pennsylvania), and each contains 27 mg of elemental iron. A placebo was included in the study for the control group in this crossover, single-blind study.
  
  
  RESULTS
  The net iron bioavailability (mean +/- SE) of Stuartnatal Plus and Materna, accounting for diurnal variation, and the iron ingested with the standardized meal was 5.4 +/- 0.4 and 4.6 +/- 0.2 mg, respectively, while fasting and 2.9 +/- 0.4 and 2.7 +/- 0.4 mg, respectively, postprandially. The total amount of iron absorption in the fasting states from both prenatal formulations exceeded the 3 mg of supplemental iron absorption per day recommended by the National Academy of Sciences.
  
  
  CONCLUSIONS
  The results of this study indicate that these two prenatal multivitamin/multimineral formulations provide > 3.0 mg of supplemental iron absorption (fasting) as recommended by the National Academy of Sciences and 2.7 mg of iron absorption above the levels achieved following ingestion of a standard, low-iron test meal.
authors.affiliation: Department of Obstetrics and Gynecology, University of Texas Medical Branch at Galveston 77555-0587, USA. ebdawson@utmb.edu
authors.forename: E B
authors.initials: EB
authors.lastname: Dawson
authors.forename: D R
authors.initials: DR
authors.lastname: Evans
authors.forename: W J
authors.initials: WJ
authors.lastname: McGanity
authors.forename: M E
authors.initials: ME
authors.lastname: Conway
authors.forename: D D
authors.initials: DD
authors.lastname: Harrison
authors.forename: F M
authors.initials: FM
authors.lastname: Torres-Cantu
mesh_terms: D000328:Adult; D001682:Biological Availability; D018592:Cross-Over Studies; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007501:Iron / Q000097:blood / Q000493:pharmacokinetics*; D018673:Nutrition Policy; D011247:Pregnancy / Q000378:metabolism*; D012016:Reference Values; D016037:Single-Blind Method
chemical_list: D007501:Iron