Heavy menstrual bleeding is common in exercising women and linked to self-reported anaemia and perceived performance loss
Screen iron status
Participants
n=1862 exercising females in total: 789 responded to the online survey and 1073 completed the survey at the marathon.
Protocol
'Female Health Questionnaire' with a validated diagnostic HMB series, demographics, exercise ability, training status, anaemia, iron supplementation and whether the menstrual cycle had affected training/performance; stage 1 online (social media), stage 2 face-to-face with runners registered for the 2015 London Marathon.
Key Findings
Heavy menstrual bleeding (validated diagnostic HMB series) reported by 54% online / 36% of marathon runners; also prevalent among elite athletes (37%).
Overall 32% reported a history of anaemia; 50% had previously supplemented with iron; HMB was associated with self-reported anaemia, more iron supplementation, and a perceived negative impact on training/performance.
Only 22% had sought medical advice — a large under-recognised, treatable driver of iron loss.
Practical Application
Two-stage survey, n=1862 exercising women: heavy menstrual bleeding was reported by 54% online and 36% of London Marathon runners (37% of elite athletes); 32% had a history of anaemia, 50% had used iron, and only 22% had sought medical advice — HMB is common, associated with self-reported anaemia and perceived performance loss, and mostly unmanaged.
Add a simple HMB question to female-athlete intake. Not from this paper; the base's own practice: flags such as frequent flooding/clots, hourly protection changes, or periods lasting more than 7 days. A positive screen = red flag for iron depletion.
For HMB and/or endurance underperformance/fatigue, recommend clinician-ordered ferritin + iron panel rather than empirical self-supplementation; refer to GP/gynaecologist.
Frame HMB as medical/manageable, not "push through".
Limitations
Self-report (recall/selection bias); anaemia self-reported not lab-confirmed; cross-sectional (association not causation); the iron→endurance mechanism comes from other sources.
How this entry was checked and changed
Why this level
(cross-sectional, self-report)
Content correction 2026-09-27
Type line listed "n=789; n=1073" separately so the parser read n=789; total n=1862 (789 + 1073) now stated first in a Participants section.
HMB screening criteria (hourly protection changes, >7 days) labelled as the base's own practice — not from this paper. Lead rewritten to the study's numbers; Sport line set to "running, general".
Cross-references to duplicate stubs repointed to their canonical entries (REF-526->REF-335); the stubs were emptied on 2026-09-27.