Findings from a new study showed that female firefighters with post-traumatic stress disorder and anxiety had significantly lower levels of anti-Müllerian hormone, a key marker of ovarian reserve.

Researchers analyzed 250 female firefighters younger than age 45 years between September 2020 and September 2022, discovering that those with clinically diagnosed post-traumatic stress disorder (PTSD) had 66% lower anti-Müllerian hormone (AMH) levels compared to those without the condition. Women with anxiety diagnoses showed 33% lower AMH levels.

"The observed magnitude of association between PTSD and AMH (66% lower AMH levels among those with a history of PTSD in our study) is larger than many other environmental exposures known to reduce AMH levels," the study authors wrote in the Journal of Women's Health.

The effect was particularly pronounced in firefighters aged 35 to 45 years, where PTSD was associated with 82.5% lower AMH levels and anxiety with 72.2% lower AMH levels.

While depression was also studied, its association with reduced AMH levels did not reach statistical significance in the overall population. However, among firefighters who had at least one pregnancy, depression was significantly associated with lower AMH.

The study population included both recruits (35.2%) and incumbent firefighters (64.4%), with a mean age of 32.5 years. Clinical diagnoses were depression in 15%, anxiety in 18.2%, and PTSD in 8.7%.

The researchers suggested chronic inflammation may be the mechanism linking mental health conditions to reduced ovarian reserve, noting that previous studies have shown elevated inflammatory markers in individuals with PTSD.

Study limitations included its cross-sectional nature, reliance on self-reported diagnoses, and inability to account for effects of pharmacological treatments for mental health conditions. The COVID-19 pandemic may have also impacted the incidence of mental health conditions in this first responder population during the study period.

The findings highlight the potential biological mechanisms through which mental health conditions may influence reproductive health in female firefighters, who experience higher rates of PTSD than their male counterparts (20% versus 12%).

The authors declared no conflicts of interest.