Clot Risk with Non-Oral Hormonal Contraception

Given that many people find remembering to take daily medications difficult, the convenience of the contraceptive patch (changed weekly) and ring (changed monthly) is an advantage. To assess whether these forms of contraception affect risk for venous thromboembolism (VTE), investigators analyzed data from more than 1,600,000 nonpregnant Danish women (age range, 15–49) without histories of thrombotic disease or cancer. Prescription records were used to identify users of hormonal contraception during the study period (2001–2010).

Absolute rates of confirmed VTE were low among current users of the patch (9.7 per 10,000 woman-years of use) and the ring (7.7 per 10,000 woman-years). However, adjusted analysis showed that relative risk for VTE in …