Absorption of Heme and Non-Heme Iron in Pregnant and Non-pregnant Women and Mechanisms of Fetal Iron Transfer
The three specific aims of this study are 1) to assess the impact of iron status on relative differences in absorption of heme and non-heme iron among pregnant women and non-pregnant women, 2) to assess the magnitude and the determinants of heme and non-heme iron transfer to the fetus over the last trimester of pregnancy, and 3) to characterize relationships between placental iron binding proteins with the enrichment of stable iron isotopes in the neonate at birth. The investigators hypothesize that there will be up regulation of heme and non-heme iron absorption and up regulation of placental iron transport proteins in response to low maternal iron stores.
|Study Design:||Observational Model: Case-Only
Time Perspective: Prospective
|Official Title:||Absorption of Heme and Non-Heme Iron in Pregnant and Non-pregnant Women and Mechanisms of Fetal Iron Transfer|
- Heme and Non-Heme Iron Absorption [ Time Frame: two-weeks post dosing (3rd trimester for pregnant subjects) ] [ Designated as safety issue: No ]
- Heme and Non-Heme Transfer to Fetus [ Time Frame: Delivery ] [ Designated as safety issue: No ]
- Iron Status (serum ferritin, TfR, Total Body Iron, Hb, Hepcidin), Folate, B-12, CRP and EPO in women and neonates [ Time Frame: two weeks post dosing and at delivery for pregnant subjects ] [ Designated as safety issue: No ]
- Protein expression of key iron transport proteins. [ Time Frame: Delivery ] [ Designated as safety issue: No ]
Biospecimen Retention: Samples With DNA
For non-pregnant subjects 15 mL of blood are collected. For pregnant subjects two 15 mL blood samples are collected. The placenta and up to 30 mL of cord blood are also collected at delivery.
|Study Start Date:||May 2008|
|Study Completion Date:||July 2011|
|Primary Completion Date:||July 2011 (Final data collection date for primary outcome measure)|
To measure the absorption of heme and non-heme iron in women, pregnant and non-pregnant women will consume a standardized meal of pork (intrinsically labeled with 58Fe) and a second meal of non-heme 57Fe (as ferrous sulfate). Two weeks after ingesting these test meals, a blood sample will be collected from each women and the amount of heme (58Fe) and non-heme (57Fe) iron incorporated into red blood cells will be measured with magnetic sector thermal ionization mass spectrometry. Cord blood samples and placental tissue will be obtained at delivery to measure how these two forms of dietary iron were transferred across the placenta to the fetus. Maternal and neonatal iron status and placental proteins involved in iron transport will also be measured. Data from this study will provide information that aims to improve human health by better understanding the iron requirements of a population at high risk of iron deficiency.
|United States, New York|
|Strong Memorial Hospital|
|Rochester, New York, United States, 14642|
|Rochester, New York, United States, 14620|
|Principal Investigator:||Kimberly O O'Brien, PhD||Cornell University|
|Principal Investigator:||Eva Pressman, MD||University of Rochester|