In this case, the patient’s abdominal pain was caused by superior mesenteric and portal vein thrombosis, which is probably due to prolonged use of oral contraceptive pills by exclusion of other risk factors. This thromboembolic phenomenon is an uncommon disease that carries a significant morbidity and mortality rate. This may be considered in the differential diagnosis of abdominal pain in child bearing women on oral contraceptive, especially those who have been using the medication for more than one year and have personal history of deep venous thrombosis without the usual risk factors.
The mechanisms accounting for thrombogenicity in oral contraceptive users remain unclear but may correlate with the dose of estrogen. It has been postulated that oral contraceptives induce the following:
- hypercoagulable state by acceleration of the internal and external pathways of the coagulation cascade or by reduction of Antithrombin III levels
- antifibrinolytic activity by decreasing spontaneous fibrinolysis
- intimal hyperplasia
Management options for superior mesenteric and portal vein thrombosis include systemic anticoagulation, endovascular infusion of thrombolytic agents, and surgical thrombectomy. Surgery is required in patients with intestinal infarction. In patients without intestinal infarction, endovascular thombolysis or thrombectomy is an option. Risks of a thromboembolic complication decrease within 1 month of discontinuing the oral contraceptive.