A 15-yr-old girl presented with bilateral gross ovarian tumors, clinical features of long-standing unrecognized hypothyroidism and markedly elevated CA-125 levels. Ovarian resection was avoided, as the presentation was consistent with the Van Wyk and Grumbach syndrome; and the patient was treated with replacement of thyroid hormone. Regression of the ovarian tumors occurred 6 months after initiation of the treatment. The authors emphasise the need for increased awareness and screening for hypothyroidism in patients with ovarian tumors, in order to prevent inadvertent operative interventions.