A 32-year-old woman on combined oral contraceptive pills (COCPs) develops sudden pleuritic chest pain and dyspnea on day 10 of a new 7-day immobilization due to leg fracture. The most likely complication and its mechanism related to OCP use is:
- A Spontaneous pneumothorax — COCPs cause pleural effusion
- B Pulmonary hypertension from estrogen-induced vasoconstriction
- C Pulmonary embolism — COCPs increase VTE risk 3–5 fold by increasing clotting factors II, VII, X and fibrinogen, and decreasing protein S ✓
- D Pleuritis from immune activation by progestin component
Explanation
Combined oral contraceptives increase venous thromboembolism (VTE) risk by 3–5 fold through estrogen-mediated upregulation of hepatic coagulation factors (II, VII, VIII, X, XII, fibrinogen) and decreased natural anticoagulants (protein S, protein C activity indirectly). Immobilization post-fracture compounds VTE risk multiplicatively. The clinical picture — sudden pleuritic pain and dyspnea after immobilization — is classic pulmonary embolism. Current COCPs are absolute contraindicated in patients with prior VTE, and COCPs should be stopped pre-electively before major surgery/prolonged immobilization.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.