Delayed pulmonary embolism following oocyte retrieval in invitro fertilization: A neglected risk factor for thromboembolic events?

Abstract Introduction: Pulmonary embolism (PE) is a rare complication that is often underdiagnosed following assisted reproductive technology (ART), particularly in vitro fertilization (IVF). Due to the nonspecific symptoms, delayed diagnosis is a common challenge, especially when clinical presentation occurs weeks after the procedure. In ART patients, the risk of PE is increased due to hormonal alterations and other procedural factors. However, delayed diagnosis remains an overlooked issue in this patient population. This case highlights the challenges that are associated with delayed diagnosis of PE and the management of an IVF patient who developed bilateral segmental PEs one month post-oocyte retrieval. Case Presentation: A 34-year-old African American woman with no past medical history and a BMI of 24 underwent an uncomplicated transvaginal ultrasound-guided oocyte retrieval as part of her IVF cycle, yielding 13 oocytes with no complications, and there were no signs of ovarian hyperstimulation syndrome (OHSS). She had no prior or family history of thrombophilia, venous thromboembolism, or known clotting disorders. One month post-procedure, she presented to the emergency department with sudden onset pleuritic chest pain that radiated to the back, dyspnea, fatigue, and hemoptysis. A computed tomography pulmonary angiography confirmed bilateral segmental pulmonary emboli, but lower extremity Doppler studies were negative for deep vein thrombosis. There were no provoking factors other than recent hormonal stimulation. Thrombophilia screening, including antithrombin III, protein C, protein S, and factor V Leiden, were all negative. Treatment: The patient was managed with intravenous heparin with a subsequent transition to apixaban after stabilization. The patient recovered fully and was discharged in stable condition with no further complications. Apixaban was continued for three months with no reoccurrence. The hypercoagulation workup done after completion of anticoagulation was negative. Hematology recommended thromboprophylaxis for future ART cycles to prevent further thromboembolic events. Discussion: Delayed diagnosis of PE is a rare significant complication in ART patients due to the overlap of other common post-procedural complaints with PE symptoms. In this case, the patient's presentation occurred one month post-oocyte retrieval, making the diagnosis particularly challenging. Despite the absence of classic risk factors, PE was found on CTPA, highlighting the need for increased clinical suspicion in ART patients, particularly those presenting with atypical symptoms. This case emphasizes the importance of early diagnosis and management, including the use of anticoagulation therapy, in preventing short-term mortality and morbidity. Additionally, it raises the question of the role of thromboprophylaxis in ART patients, particularly those with additional risk factors such as age, obesity, and prior IVF attempts. Previous studies have shown that while delayed PE diagnosis does not always result in long-term mortality impacts. Short-term outcomes, including higher in-hospital mortality and morbidity, are adversely affected. Also, PE has been shown to occur due to alterations in hormones resulting in an imbalance between the procoagulants and anticoagulants. PE in ART patients may be underdiagnosed because its presentation often overlaps with some other post-procedural complaints such as fatigue or chest discomfort, leading to missed diagnoses or delays in care. It is important that ART patients be monitored closely for signs of PE as soon as treatment is started, and there should also be regular follow-up. Even if they present weeks after their procedure, there should also be high suspicion for PE. Conclusion: This case highlights the diagnostic dilemma and management of delayed PE in ART patients. It emphasizes the importance of early recognition and the need for a high index of suspicion for PE, even in the absence of classic risk factors. Prophylactic anticoagulation may be beneficial in ART patients who are at high risk to prevent thromboembolic events, particularly in those with additional risk factors. Clinicians must remain watchful in diagnosing PE early to improve short-term outcomes and reduce mortality. Future research should focus on and investigate the role of routine thromboprophylaxis in ART patients and screening to reduce the incidence of PE and improve patient outcomes.