Gender-affirming hormone therapy in the transgender patient: influence on thrombotic risk

Research regarding the hematologic sequelae of estrogen and testosterone therapy for transgender people is an emerging area. While estrogen therapy has been widely studied in cisgender women, studies in transgender individuals are limited, revealing variable adverse effects influenced by the dose and formulation of estrogen used. Thrombotic risk factors in transgender and gender-diverse individuals are multifactorial, involving both modifiable and nonmodifiable factors. Management of venous thromboembolism (VTE) in individuals receiving gender-affirming estrogen entails standard anticoagulation therapy alongside shared decision-making regarding hormone continuation and risk factor modification. While data and guidance from cisgender women can offer a reference for managing thrombotic risk in transgender individuals on hormone therapy, fully applying these insights can be challenging. The benefits of gender-affirming hormone therapy include significantly reducing the risk of suicide and depression, highlighting the importance of a contemplative approach to the management of hormonal therapy after a VTE event. Although limited, the available data in the literature indicate a low thrombotic risk for transgender individuals undergoing gender-affirming testosterone therapy. However, polycythemia is a common adverse effect necessitating monitoring and, occasionally, adjustments to hormonal therapy. Additionally, iron deficiency may arise due to the physiological effects of testosterone or health care providers' use of phlebotomy, an aspect that remains unstudied in this population. In conclusion, while the set of clinical data is expanding, further research remains vital to refine management strategies and improve hematologic outcomes for transgender individuals undergoing gender-affirming hormone therapy.