Iron Absorption and Requirements in Pregnancy and Lactation

NCT05973552 | Recruiting

• 1 other identifier: PILLAR_II
• Study Type: observational
• Target: 250
• Locations: 1 country
• Sites: 1

Brief 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

Outcome Measures

Primary Outcomes (6)

• Iron absorbed, lossed and gained in the first trimester

  isotope dilution

  Change in 57Fe tracer abundance between gestational age 6, 10 and 15 weeks

• Iron absorbed, lossed and gained in the second trimester

  isotope dilution

  Change in 57Fe tracer abundance between gestational age 15, 20 and 25 weeks

• Iron absorbed, lossed and gained in the third trimester

  isotope dilution

  Change in 57Fe tracer abundance between gestational age 25, 30 and 35 weeks

• Iron absorbed, lossed and gained throughout pregnancy

  isotope dilution

  Change in 57Fe tracer abundance between gestational age 6, 10, 15, 20, 25, 30 and 35 weeks

• Iron absorbed, lossed and gained in lactating women

  isotope dilution

  Change in 57Fe tracer abundance between 6, 14 and 24 weeks postpartum

• Iron absorbed, lossed and gained in infancy

  isotope dilution

  Change in 57Fe tracer abundance between age 6, 14 and 24 weeks

Secondary Outcomes (102)

• Fractional iron absorption (%) in the second trimester

  gestational age 20 weeks

• Fractional iron absorption (%) in the third trimester

  gestational age 30 weeks

• Erythrocyte iron incorporation (%) in the second trimester

  gestational age 20 weeks

• Erythrocyte iron incorporation (%) in the third trimester

  gestational age 30 weeks

• Hemoglobin concentration (g/dl)

  gestational age 6 weeks

Study Arms (2)

All participants

Women (n=250), are followed throughout their pregnancy. Mother-infant pairs are followed throughout the first 6-months postpartum. Women receive daily oral iron supplementation during pregnancy in accordance with local standards of care. Using the stable iron isotopes dilution methodology, concentration of the stable iron isotope tracer (57Fe) in circulation will be measured throughout pregnancy and up to 6 months postpartum in both, mother and infant.

Other: CO-rebreathing

Randomly selected sub-group

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. Oral iron absorption and erythrocyte iron incorporation will be measured 14 days after tracer administration.

Other: CO-rebreathing; Other: Oral iron isotope administration (54Fe); Other: Intravenous iron isotope administration (58Fe)

Interventions

CO-rebreathing OTHER

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

All participants; Randomly selected sub-group

Oral iron isotope administration (54Fe) OTHER

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

Randomly selected sub-group

Intravenous iron isotope administration (58Fe) OTHER

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

Randomly selected sub-group

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

This study will recruit 250 pregnant women in the first trimester who previously participated in a stable iron isotope study (Clinical Trial ID: NCT05266703) and received 15 mg of the stable iron isotope 57Fe as an oral dose of ferrous sulphate at least 12 months before being enrolled in this trial.

You may qualify if:

• Providing consent to the informed consent form
• Positive pregnancy test and gestational age \<10 weeks based on history of last menstrual period
• Permanent residence in the study area, and not expected to leave the study site for more than 4 weeks over the following 16 months
• Assessment of good health by professional staff at Msambweni Hospital

You may not qualify if:

• Pre-pregnancy body mass index \>30 kg/m2
• Blood transfusion or intravenous iron treatment within 4 months of study start
• Major chronic infectious disease (e.g., tuberculosis, HIV+, hepatitis)
• Major chronic non-infectious disease (e.g., Type 1 or 2 diabetes, cancer)

Sponsors & Collaborators

• University of Oxford: lead
• Columbia University: collaborator
• Jomo Kenyatta University of Agriculture and Technology: collaborator
• Msambweni County Referral Hospital: collaborator
• ETH Zurich: collaborator

Study Sites (1)

Msambweni Referral Hospital

Msambweni, Kenya

RECRUITING

MeSH Terms

Conditions

Breast Feeding

Condition Hierarchy (Ancestors)

Feeding Behavior; Behavior

Central Study Contacts

Nicole Stoffel, PhD

CONTACT

+41446328393; nicole.stoffel@rdm.ox.ac.uk

Joyce Wali, BSc

CONTACT

+254704862877; stellawali507@gmail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 18, 2023
• First Posted: August 3, 2023
• Study Start: July 31, 2023
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: August 3, 2023

Record last verified: 2023-06

Data Sharing

• IPD Sharing: Will not share

Locations

KE (1)