# Iron mother- protocol for a randomised controlled trial of daily versus alternate day ferrous fumarate for the treatment of iron deficiency anaemia in pregnancy

**Authors:** F.E. O'Toole, F.M. McAuliffe, J.M. Fitzgerald, G.A. Mealy, R. Petkute, L.A. Bolger, A. Murphy-Cruse, B. Soldati, M. Galligan, J.M. Walsh

PMC · DOI: 10.1016/j.conctc.2025.101447 · Contemporary Clinical Trials Communications · 2025-02-03

## TL;DR

This study compares daily and alternate-day iron supplements for treating anemia in pregnancy to find the most effective and tolerable option.

## Contribution

The study introduces a non-inferiority trial comparing daily and alternate-day iron dosing for iron deficiency anemia in pregnant women.

## Key findings

- Alternate-day iron dosing may be as effective as daily dosing for treating anemia in pregnancy.
- The trial will assess compliance, tolerance, and hemoglobin levels at term as secondary outcomes.

## Abstract

Iron deficiency anaemia (IDA) is the commonest haematological problem in pregnancy and has implications for maternal, fetal, and childhood health. Treatment, despite being inexpensive and readily available, remains challenging with issues relating to compliance, tolerability, and effectiveness. There is a lack of consensus regarding the optimal dosing of oral iron replacement in pregnancy. Emerging evidence from non-pregnant populations suggest that alternate day dosing may be as effective.

We propose a phase IV open label randomised controlled non-inferiority trial of daily versus alternate day ferrous fumarate for a 4-week period for the treatment of confirmed iron deficiency anaemia in pregnancy. Our study population comprises singleton pregnancies between 14+0- and 34+0-weeks’ gestation with a haemoglobin (Hb) of <10.5g/dL and a ferritin of <30μg/L. The intervention is alternate day ferrous fumarate 305mg (100mg elemental iron) and the comparator is daily ferrous fumarate 305mg. The primary endpoint, change in Hb from randomisation to week 4, will be analysed by linear regression, adjusting for baseline Hb level. Analysis will be conducted by intention-to-treat analysis with per protocol sensitivity analysis. Sample size was calculated on the assumption of no difference between primary endpoint means, a Type 1 error rate of 0.025, a power of 90 %, a standard deviation of 0.83 g/dL and a non-inferiority margin of −0.4 g/dL. Under these assumptions, 92 subjects per treatment arm would be required to test for non-inferiority.

We hypothesise that alternate day iron in pregnancy will be as effective as daily iron for the treatment of iron deficiency anaemia.

•Randomised controlled trial of daily versus alternate day oral iron for the treatment of anaemia in pregnancy.•Inclusion criteria: singletons with haemoglobin < 10.5g/dL and ferritin < 30μg/L between 14+0 and 34+0 weeks gestation•Non-inferiority study with a non-inferior margin of -0.4g/dL haemoglobin difference between the two arms.•Secondary outcomes include compliance, tolerance, and haemoglobin levels at term

Randomised controlled trial of daily versus alternate day oral iron for the treatment of anaemia in pregnancy.

Inclusion criteria: singletons with haemoglobin < 10.5g/dL and ferritin < 30μg/L between 14+0 and 34+0 weeks gestation

Non-inferiority study with a non-inferior margin of -0.4g/dL haemoglobin difference between the two arms.

Secondary outcomes include compliance, tolerance, and haemoglobin levels at term

## Linked entities

- **Chemicals:** ferrous fumarate (PubChem CID 6433164)
- **Diseases:** iron deficiency anaemia (MONDO:0001356)

## Full-text entities

- **Diseases:** IDA (MESH:D000090463)
- **Chemicals:** ferrous fumarate (MESH:C031621), Iron (MESH:D007501)

## Full text

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## Figures

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## References

41 references — full list in the complete paper: https://tomesphere.com/paper/PMC11872400/full.md

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Source: https://tomesphere.com/paper/PMC11872400