Iron Absorption and Requirements in Pregnancy and Lactation

Summary

Iron requirements increase significantly during pregnancy. Current recommendations for iron intake in pregnant and lactating women (PLW) are mainly based on factorial estimates and extrapolated from non-PLW. High-quality quantitative data on iron requirements in PLW are lacking, particularly in Sub- Saharan Africa where anaemia and infections are common.

The primary objective of this study is to use the stable iron isotope technique to determine iron requirements and assess iron absorption and losses in PLW living in Kenya.

In this prospective observational study, we will enrol pregnant women in the first trimester (n = 250) from a previous study cohort (n=1000) who participated in an iron absorption study at least 12 months ago and received the stable iron (Fe) isotope 57Fe. This 57Fe has now distributed and equilibrated throughout the women's body iron. Once enrolled in the present study, following Kenyan guidelines, women will receive standard prenatal care, including routine daily iron and folate supplementation. We will collect venous blood samples in each trimester and at delivery, and during the first 6 months of lactation in the mothers and infants (heel prick samples). To directly assess dietary iron absorption, in a randomly selected subset of women (n=35), oral and intravenous stable iron isotope tracers (54Fe, 58Fe) will be administered in the 2nd and 3rd trimesters.

Conditions

• Iron Requirements
• Pregnancy
• Lactation
• Infancy
• Iron Absorption

Interventions

OTHER

CO-rebreathing

In the CO-rebreathing method, a dedicated apparatus is used for inhaling and rebreathing a very small bolus of CO through a spirometer for \~2 min, which is absorbed through the lungs and binds to Hb, and then the increase of HbCO content of blood is measured 8 min after the CO inhalation. The increase of COHb in blood samples can then be used to precisely calculate Hb mass and blood volume

OTHER

Oral iron isotope administration (54Fe)

Participants randomly assigned to the sub-group, will receive 54Fe with a test meal in the second and third trimester for assessment of dietary iron absorption

OTHER

Intravenous iron isotope administration (58Fe)

Participants randomly assigned to the sub-group, will receive intravenous 58Fe in the second and third trimester for assessment of erythrocyte iron incorporation

Sponsors & Collaborators

• Columbia University

  collaborator OTHER

• Jomo Kenyatta University of Agriculture and Technology

  collaborator OTHER

• Msambweni County Referral Hospital

  collaborator UNKNOWN

• ETH Zurich

  collaborator OTHER

• University of Oxford

  lead OTHER

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-07-31

Primary Completion

2026-06-30

Completion

2026-09-01

Countries

• Kenya

Study Locations