A study has revealed female athletes aged 18-40 are up to eight times more likely to sustain an anterior cruciate ligament (ACL) injury compared to male athletes.
There have been suggestions of a link between the menstrual cycle and hormonal fluctuations at the time of injury.
Injuries to the ACL are particularly common in sports like basketball, soccer, and netball where awkward and explosive movements place the ligament under significant stress.
What are the studies saying?
Researchers suggest that women are more susceptible to an ACL injury during the late follicular phase and the ovulatory phase of their menstrual cycle, where oestrogen levels spike.
Oestrogen increases the strength and elasticity of ligaments, and is at its lowest when menstruating. Ligaments like the ACL don’t have as much ‘give’ during this peak.
Graph by Jessica Freeman (Source: National Library of Medicine)
University of Wollongong (UOW) student Freya Spring is 11 months into recovery from a fully ruptured ACL, partially torn medial collateral ligament (MCL), and several accompanying knee fractures during a low-intensity social netball game.
“I jumped to catch a ball, came down on my knee, and heard a snap,” Ms Spring said.
Ms Spring said the constant explosive movements required in netball contributed to her injury, but also noted the injury was sustained while on day four of her period.
American former professional soccer player, Megan Rapinoe, said in her podcast last year that each of her three ACL injuries occurred while she was on her period.
Correlation or causation?
A recent framework highlights the need to integrate menstrual health into sports science, showing how performance and injury risk can vary across the cycle, and how improved understanding can better support diagnosis and care.
Research is still being conducted to confirm the link between the menstrual cycle and ACL injuries and aims to determine whether the relationship is causal or simply correlational.
