TSH-secreting pituitary tumours are rare but difficult to treat due to a combination of refractory hyperthyroidism and low surgical cure rates. We describe the case of a 21-year-old woman who, despite twin pregnancy, became euthyroid and had dramatic tumour shrinkage on octreotide treatment. To our knowledge, this is the first description of the use of octreotide for a TSH-secreting pituitary adenoma throughout pregnancy.