Female athletes are 4 to 8 times more likely to tear an anterior cruciate ligament (ACL) than male athletes. With over 2000 ACL injuries in female athletes reported annually, ACL tears are a common injury. Often the ACL injuries in female athletes occur during non-contact or non-external force activities. That is, these injuries occur during regular practices or games in the absence of a collision or direct hit injury. In contrast, male ACL tears are more often the result of a fall or collision (football or skiing injuries, for example).
As many women might suspect or intuit, the menstrual cycle and associated hormone changes have much influence on when female athletes are likely to experience ligament injuries, and it is not when one would think. According to research published in the American Journal of Sports Medicine, ACL injuries are significantly more likely pre-ovulation when estradiol concentrations are increasing, than post ovulation when they decline. Research suggests estradiol negatively impacts ligament strength and flexibility– making it weaker, too flexible and thus, more susceptible to rupture.