Oral Contraceptives and Deep Vein Thrombosis Are oral contraceptives a risk factor for progression to DVT in patients with undiagnosed May-Thurner anatomy?

M ay-Thurner syndrome is characterized by compression of the left common iliac vein by the right iliac artery against the fifth lumbar vertebrae.1 Although the risk of deep vein thrombosis (DVT) is increased in this setting, it is not absolute, with the incidence of DVT significantly less than the estimated incidence of this variant anatomy. It has been proposed that progression to thrombosis in May-Thurner anatomy is influenced by other factors negatively altering a patient’s coagulation profile.1-4 Oral contraceptive (OC) use is known to increase an individual’s risk of DVT, and additionally, a left-sided predominance of DVT in women on OCs has been noted. However, women with DVT on OCs are not typically evaluated for this anatomic variant. Herein, we present the case of a 16-year-old female with previously undiagnosed May-Thurner syndrome who developed acute left-sided DVT 1 month after the initiation of OC therapy. We suggest that MayThurner syndrome may be underdiagnosed and undertreated in young women in this setting.