RESUMO
Combined oral contraceptives (COC) are the most popular contraceptive method in developed countries. Since their introduction there have been numerous changes and modifications in its composition with the aim to improve safety and tolerability while maintaining contraceptive efficacy. Most of the changes have been conducted on the progestin component, since most of the combinations include ethinyl estradiol as oestrogen. One of the adverse effects of COC is the increased risk of venous thromboembolism (VTE) in two clinical forms of presentation: deep vein thrombosis or pulmonary embolism. This review details the changes in haemostasis induced by progestin-only contraceptives and the risk of VTE in women who utilize this type of contraception; the relationship with other risk factors such as thrombophilia; the interactions of these contraceptives with anticoagulant treatment and finally the eligibility criteria for the use of hormonal contraception in women with previous VTE or thrombophilia carriers.
