Vanishing large ovarian cyst with thyroxine therapy

A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the condition of the patient significantly. This case report highlights the rare and often missed association between hypothyroidism and ovarian cysts. Although very rare, profound hypothyroidism that can cause ovarian cysts in an adult should always be kept in the differential diagnosis to avoid unnecessary ovarian surgery. LEARNING POINTS: Hypothyroidism should be considered in the differential diagnosis of adult females presenting with multicystic ovarian tumours. Adequate thyroid hormone replacement therapy can prevent these patients from undergoing unnecessary and catastrophic ovarian resection. Surgical excision should be considered only when adequate thyroid replacement therapy fails to resolve ovarian enlargement. In younger women with ovarian cysts, it is also desirable to avoid unnecessary surgery so as to not compromise fertility in the future.