A 33-year-old woman presented to the emergency department (ED) with tachypnea, tachycardia, and hypoxia, complaining of dyspnea and paroxysms of dry cough for 2 days. The patient had undergone an unsuccessful in vitro fertilization procedure 1 month earlier and had had another embryo implantation 6 days earlier. She had been receiving intramuscular injections of estradiol and progesterone in sesame oil to support implantation. A chest radiograph demonstrated extensive bilateral pulmonary consolidation; a leukocytosis count of 19.7 × 10⁹ with 20% eosinophils was noted on a CBC count. A MEDLINE search yielded a case report in infertility literature describing an eosinophilic pneumonitis with similar clinical features after injections of progesterone in sesame oil. Treatment with intravenous corticosteroids was initiated in the ED, resulting in symptom and chest radiograph result improvement within 2 days and sparing the patient further imaging and antibiotic therapy.