Abstract
We report an unusual case of spontaneous ovarian hyperstimulation syndrome and pituitary hyperplasia mimicking macroadenoma in an adult, non-pregnant woman. Her condition was triggered by unrecognized primary hypothyroidism, which regressed after thyroid hormone replacement therapy. This case highlights the need for clinicians and radiologists to familiarize themselves with the clinical and imaging features detected in case of these complications of primary hypothyroidism, which are not well known in the medical and radiological profession. Such improved knowledge will help avoid delays in diagnosis, progression to life-threatening complications, and unnecessary surgery.