A 20-year-old female with congenital venous malformations in her left lower extremity had a self-limited, moderate consumption coagulopathy following angiographic studies. This episode was documented by both conventional coagulation studies and by 125l fibrinogen survival studies. It seems likely that venography triggered a local inflammation in the vascular malformations, which resulted in a localized consumption coagulopathy which abated as did the phlebitis in three weeks. We are aware of no prior reports of this complication of venography. Patients with venous malformations who undergo venography should have appropriate coagulation screening performed before and after the procedure so that any similar episode can be promptly diagnosed and treated, if treatment is deemed necessary.