Assessment of iron status in US pregnant women from the National Health and Nutrition Examination Survey (NHANES), 1999–2006

Abstract

To our knowledge, these are the first data on total body iron distributions for a representative sample of US pregnant women. Low total body iron is more prevalent in pregnant women in the second or third trimesters, in Mexican American pregnant women, in non-Hispanic black pregnant women, and in women with parity ≥2.

Iron supplement use in pregnancy – Are the right women taking the right amount?

“…8,9,11 About 1 in 5 women were consuming a daily dose of iron (≥100 mg) that in most developed countries is recommended for treatment of IDA in pregnancy. 8,9,12,17 While there are some concerns with iron excess, such as the potential for iron, as a redox-active transitional metal, to trigger oxidation stress and to cause decreased absorption of other essential divalent metal ions, such as zinc, 18 results from our study suggest very few Australian pregnant (~3%) women are at risk of consuming excess iron (>200 mg/day) from iron-containing supplements.…”

“…Both the US and UK guidelines include such advice, such as consuming iron supplements on an empty stomach, an hour before meals, with a source of vitamin C to maximize absorption and not at the same time as other medications or antacids. 8,11 Further research is needed to examine women's knowledge and beliefs around brand choice, the required amounts of iron in pregnancy supplements and also what advice healthcare professionals are providing to women about what type and dose of iron supplements to use during pregnancy.…”

“…The dose of elemental iron (in mg) consumed per week from an iron-containing supplement was calculated by adding the dosage from each iron-only or MV and mineral preparation that women reported using during the current pregnancy. To compare the amount of elemental iron consumed from iron-containing supplements with recommended doses from other developed countries, 8,11,12 the average daily dose of elemental iron from iron-containing supplements was categorised as low dose (<30 mg), preventative dose (30-65 mg), intermediary dose (66-99 mg), treatment dose (100-200 mg) and high dose (>200 mg). Due to the small numbers, to examine possible determinants of the amount of iron consumed from iron-containing supplements, categories were combined and <30, 30-99 and ≥100 mg were used to define low, preventative and treatment dosages of daily elemental iron, respectively.…”

“…7 Among developed countries, the United States, Canada, and France recommend routine iron supplementation in pregnancy with 30-60 mg of elemental iron daily. 8,9 Other developed countries, such as the United Kingdom, Germany, Norway, New Zealand, and Australia recommend selective iron supplementation; however few of these countries provide guidance on the dose of supplemental iron. 10 The UK recommends 65 mg of elemental iron daily for non-anaemic women at increased risk of iron depletion (i.e.…”

“…women with previous anaemia, multiple pregnancy, consecutive pregnancies with less than a year's interval between, and vegetarians). 11 The recommended dosage of daily elemental iron to treat IDA is 120 mg in the US, 8 100-200 mg in the UK 11 and 100 mg in Norway. 12 In Australia, there are no national guidelines that provide recommendations on dosage of iron supplementation during pregnancy.…”