Survey study, 1998
Is knee ligament injury more likely at certain phases of the menstrual cycle?
Yes. Female athletes were more likely to injure their knee ligament during the ovulatory phase and less likely during the follicular phase.
What they did
Researchers studied 40 female athletes with acute knee ligament (ACL) injuries that occurred within 3 months. Of these, 28 met the study criteria (regular periods and non-contact injury). They tracked which phase of the menstrual cycle each injury occurred in.
What they found
More ACL injuries occurred during the ovulatory phase (days 10-14 of the cycle) than would be expected by chance. Significantly fewer injuries occurred during the follicular phase (days 1-9) than expected.
What it means for you
Hormones appear to affect knee ligament stability and injury risk, with ovulation being a higher-risk time. Female athletes might use this information when planning training and competition timing. The main limit is that only 28 women met the full study criteria, and all were athletes, so it's unclear if these findings apply to all women or to non-athletes.
40
Female athletes with ACL injuries
28
Met study criteria
23
Average age in years
About the study
- Original title
- Association between the menstrual cycle and anterior cruciate ligament injuries in female athletes
- Authors
- Wojtys EM, Huston LJ, Lindenfeld TN et al.
- Journal
- The American journal of sports medicine
- Year
- 1998
- Study design
- Survey study
- Participants
- 40
- What was tested
- Observational tracking of menstrual cycle phase at time of injury
- Read the paper
- doi.org/10.1177/03635465980260050301
Topics
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