Risk Factors for Deep Vein Thrombosis in Women Aged 18 to 50: A Retrospective Analysis

BACKGROUND Deep vein thrombosis (DVT) occurs in one of every 1,000 individuals per year. Various inherited and acquired risk factors are known. We investigated the importance of oral contraceptives (OCs) as a risk factor in women of child-bearing age. OBJECTIVES To evaluate the risk factors for DVT in a female patient collective. METHODS We analyzed the records of 99 women aged 18 to 50 with DVT. We documented age, identifiable risk factor of DVT, location of the thrombus, use of OCs, and thrombophilia. RESULTS 52.5% of patients suffering from DVT were aged between 40-50 years. Forty-six patients had an unprovoked DVT; the most common risk factor was immobilization in 41. Thrombophilia was found in 18 cases. Twenty-nine patients used OCs; no influence of OCs on any of the other risk factors was found. CONCLUSIONS In our patient group, the most important risk factors were older age and immobilization. DVT is typically idiopathic and may be caused by subtle nondetectable thrombophilic disorders. The use of OCs was distributed in DVT patients just as in the general Austrian community and seems not to be a severe additional risk factor. Examining the whole lower extremity during ultrasonography is important so as not to overlook a DVT of the lower leg.