Pulmonary venoocclusive disease (PVOD) is a rare cause of pulmonary hypertension characterized by a progressive clinical course and poor outcomes if not treated by early lung transplantation. The pathogenesis of PVOD remains poorly understood. We report PVOD that developed in 2 young women soon after the initiation of oral contraceptives (OCs). The first patient is a 14-year-old girl, with no medical history, who started taking an OC 3 weeks before the onset of symptoms. The second patient is an 18-year-old girl, diagnosed 2 years previously with systemic lupus erythematosus and lupus anticoagulant, who started taking an OC 4 months before the onset of symptoms. Both patients required lung transplantation. Radiographic and histopathologic findings in both patients showed features of PVOD. Only 1 prior patient with PVOD and a handful of unclassified patients with pulmonary hypertension in association with OCs have been documented. The importance of PVOD as the basis of pulmonary hypertension in patients with connective tissue disease has been recently proposed, as well as the role of thrombogenesis, in the development of PVOD. The temporal sequence in these 2 patients suggests the thrombogenic action of OCs may contribute to the development of PVOD, with or without underlying connective tissue disease. © 2012 International Society for Heart and Lung Transplantation. All rights reserved.