Measuring Menstrual Iron Loss Using the Iron Isotope Dilution Technique

Completed

• Conditions: Iron-deficiency; Anemia; Menorrhagia
• Interventions: Other: Iron isotope dilution; Other: Alkaline hematin method

• Registration Number: NCT05788172
• Lead Sponsor: Isabelle Herter-Aeberli

Brief Summary

It is very difficult to quantify menstrual blood loss, the reference method is a tedious one. This is a problem, as it is not conducive to objectively measuring menstrual blood loss and understanding the contribution of menstrual iron loss to iron deficiency anemia. With this study, the investigators aim to investigate iron loss during the menstrual cycle and aim to validate a much simpler technique.

Detailed Description

Anemia reduction efforts have largely focused on increasing iron intakes such as improving diet quality, food fortification with iron, iron supplementation, biofortification. There is little information on the contribution of menstrual iron loss to iron deficiency anemia.

Indeed, the accurate measurement of menstrual blood loss volume and iron loss is difficult. Self-perception of heavy menstrual blood loss poorly predicts actual blood loss, and the objective measurement of menstrual blood loss remains a tedious method. Various methods have been used to objectively measure menstrual blood loss volume including radioisotopes, but these methods are invasive. The investigators aim to validate a much simpler technique, namely the stable iron isotope dilution methodology. This is a promising new method for quantifying long-term body iron balance, absorption, and loss which has not been applied previously to measure menstrual iron losses. Validating this new method against the alkaline hematin reference method would be an important step to encourage menstrual blood loss measurements and shed light on the contribution of menstrual blood loss to iron deficiency and iron deficiency anemia.

Study Timeline

• Study First Submitted: 2023-01-30
• Study Start: 2023-03-01
• Study First Submitted QC: 2023-03-14
• Study First Posted: 2023-03-28
• Primary Completion: 2023-06-29
• Study Completion: 2023-08-30
• Status Verified: 2023-11
• Last Update Submitted: 2023-11-21
• Last Update Posted: 2023-11-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 10

Inclusion Criteria

• Female, 18-30 years old
• Already labelled with stable iron isotopes at least 12 months prior to study start
• Weight <70 kg
• Normal body mass index (18.5 - 25kg/m2)
• Regular menstrual cycle (self-reported cycle length between 28 and 35 days in the past 6 months)
• Signed informed consent
• Able to read and understand English

Exclusion Criteria

• Use of hormonal contraceptives within a 3-month recall period
• Anemia (hemoglobin < 117 g/L)
• Any known major metabolic, gastrointestinal, kidney or chronic disease such as diabetes, renal failure, hepatic dysfunction, hepatitis, hypertension, cancer, or cardiovascular diseases (according to the participants own statement)
• Women with severe menstrual cramps
• Consumption of iron-containing supplements within 1 month prior to the start of study
• Known difficulties with blood sampling
• Pregnancy (serum human chorionic gonadotropin (hCG) < 5 mIU/mL)
• Current smoking (>1 cigarette per week over a 1-month recall period)
• Women who are planning to get pregnant
• Inability to follow the study protocol

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Participants	Iron isotope dilution	Female 18-30 year olds, who have already been labelled with stable iron isotopes at least 12 months prior to study start.
Participants	Alkaline hematin method	Female 18-30 year olds, who have already been labelled with stable iron isotopes at least 12 months prior to study start.

Primary Outcome Measures

Name	Time	Method
Change in isotopic ratio per cycle	Screening, day 1, 8, 15, 22, 29, 36, 43, 50, 57, 64, 71, 78 and 85	The change in iron losses between the time of menstruation and the remaining duration of the cycle will be measured based on the dilution of the stable iron isotopes in the blood
Amount of menstrual blood lost (mL/cycle)	At the beginning of menstrual cycle 3 (cycle length between 28 and 35 days)	The amount of menstrual blood lost will be determined using the alkaline hematin reference method. All sanitary material is collected during menstruation in each cycle and the amount of blood lost is measured directly in this material. For each cycle the total amount of blood lost during this cycle is determined (there will be one value only during each cycle).

Secondary Outcome Measures

Name	Time	Method
Hemoglobin concentration (g/L)	Screening, day 1, 8, 15, 22, 29, 36, 43, 50, 57, 64, 71, 78 and 85	Hemoglobin will be measured to determine the presence of anemia and for the standardization of menstrual blood loss measurement
Serum transferrin receptor (mg/L)	Day 1 and 85	Iron status parameter
C-reactive protein (mg/L)	Day 1 and 85	Acute inflammation parameter
Serum ferritin (microg/L)	Day 1 and 85	Iron status parameter
Alpha-1-acid glycoprotein (g/L)	Day 1 and 85	Chronic inflammation parameter

Trial Locations

Locations (1)

ETH Zurich; 🇨🇭 Zurich, Switzerland