May-Thurner syndrome complicating pregnancy: a report of four cases.

Abstract May-Thurner syndrome is a common anatomic variant associated with deep venous thrombosis. There are few reports describing implications for and management in pregnancy. We performed a retrospective review and description of 4 women with May-Thurner syndrome receiving complete or consultative obstetrical care in our practice. Presentations included (1) previous stroke from presumed paradoxical embolus, (2) chronic lower extremity venous congestion treated prepregnancy with stenting, (3) prior iliac thrombosis treated with thrombolysis, anticoagulation, and stenting, and (4) active third trimester iliac thrombosis. The first 3 patients received prophylactic anticoagulation, while the fourth was fully anticoagulated. May-Thurner is an underappreciated cause of deep venous thrombosis in reproductive-aged women. Awareness may lead to improved recognition, treatment, and fewer long-term sequelae.