Women's and Transgender Issues in Thrombosis and Hemostasis: Laboratory Parameters of Coagulation and Fibrinolysis Influenced by Hormones, Including Pregnancy and Postpartum.

Exogenous estrogen, commonly in the form of combined hormonal contraceptives and menopausal hormone therapies, is associated with changes in coagulation proteins leading to increased risk of venous thromboembolism (VTE). Similarly, this prothrombotic milieu is recreated in pregnancy due to elevations of endogenous estrogen and progesterone. Endogenous elevations of these hormones decrease in the postpartum setting. Exogenous estrogen is also used as gender-affirming hormonal therapy with transgender women, but data on its thrombotic risk in this demographic are limited.