THROMBOSIS SECONDARY TO MEDROXYPROGESTERONE IN PATIENT AT RISK FOR THROMBOEMBOLISM
Michael C Ward, Devin A King, Mirranda Link, Rodel R Gloria, James R Taylor, and Kristin Wiisanen Weitzel

OBJECTIVE: To report a case in which a young woman receiving medroxyprogesterone acetate injections developed deep vein thrombosis (DVT) after prolonged travel.

CASE SUMMARY: An obese 27-year-old African American woman who had been receiving medroxyprogesterone acetate injections 150 mg intramuscularly every 3 months for 6 years experienced DVT after a 56-hour car ride. The patient's known risk factors for DVT included immobility, obesity (140 kg), and medroxyprogesterone acetate therapy. Family and personal history for thrombotic events were denied. Tests were performed after detection of the DVT to assess the patient for anticoagulation defects; results revealed an unidentified underlying protein S deficiency. All other test results were within normal limits.

DISCUSSION: Based on the Naranjo probability scale, it is possible that the DVT experienced by our patient was due to medroxyprogesterone acetate. Although she did have other risk factors for DVT, her underlying protein S deficiency was diagnosed after the thrombosis. Literature describing the relationship between the injectable form of contraception and thrombosis is limited. Therefore, this report reviews protein S deficiency, the relationship between oral contraceptives (OCs) and thrombosis, the influence of immobility on thrombosis development, and the clinical implications of evaluating patients for underlying inherited clotting abnormalities before initiating OCs.

CONCLUSIONS: When considering whether to prescribe contraceptives, clinicians should assess the patient's risk factors for thrombosis, such as family or personal history. Although generally not recommended, prescreening tests may be considered if there is a positive family or personal history.

J Pharm Technol 2005;21:276-80.