When asked if this is enough data to recommend oral contraceptives to prevent ACL injuries, Steven F. DeFroda, M.D., M.E., Orthopaedic Trauma Fellow at Brown University/Rhode Island Hospital and lead researcher on the study told OTW, “It’s important to stress that we aren’t explicitly ‘recommending’ the use of oral contraceptives for the prevention of ACL injuries. As our study was retrospective in nature, it is subject to certain limitations, however our findings did support a trend within literature that regulating estrogen and progesterone levels could lead to a decrease risk of ACL injury (although the jury is certainly still out as to the optimal formulation) and if this is a causative effect or just a confounder within these groups.
“At this time the data we have suggests that it is a potential side benefit, and this should warrant a discussion point for both active patients and their primary care doctors in the event that patients are already considering oral contraceptives.”
He added that there are side effects to taking oral contraceptives—weight gain and blood clots—so they wouldn’t recommend it for the sole purpose of ACL preventions, but would encourage a female patient to discuss the pros and cons of this medication with their prescribing physician.
“We are currently interested in examining which formulations of oral contraceptives may best offer the protective effect. We have ongoing research examining low versus high estrogen medications and low versus high progesterone medications (also retrospective in nature),” he said.
What about sex differences in other injuries?
When asked if the risk for other orthopedic injuries could also be linked to a woman’s menstrual cycle, he said that this question was of great interest to him and his colleagues.
He said, “Relaxin is a hormone that also circulates at higher levels in females. We mention that this hormone does seem to align with risk of ACL injury. Our sports injury research team has examined the effects of this hormone on shoulder instability and was unable to find a similar association, so the short answer is the jury is still out!”
“It has obviously been well documented that elderly females are at a higher risk of osteoporosis and fragility fracture due to decreasing bone mineral density once estrogen levels drop following menopause, and there are well documented links regarding the ‘female athlete triad’ (now being referred to as Relative Energy Deficiency in Sports Syndrome RED-S Syndrome by some) commonly effecting endurance females and consisting of amenorrhea, some form of eating disorder or energy deficient state and stress fracture, but to our knowledge nothing explicitly related to the menstrual cycle, at least nothing as widely studied as the ACL.”
