NON-FUNCTIONING PITUITARY ADENOMA COMPLICATING PREGNANCY

Abstract

INTRODUCTION
Pregnancies are rare in women with pituitary adenoma. We describe a patient with non-functioning pituitary adenoma who had spontaneous pregnancy. She developed progressive worsening of vision and underwent successful transsphenoidal surgery (TSS) in the second trimester.

CASE
A 35-year-old female presented with secondary amenorrhoea and galactorrhoea for 6 months. A large pituitary macroadenoma with mass effect coupled with mild increment in prolactin raised a suspicion of prolactinoma. Menstruation returned and galactorrhoea ceased following cabergoline therapy. She had a left nasal hemianopia, central hypothyroidism and hypogonadotropic hypogonadism. The other pituitary hormones were intact. Although prolactin remained suppressed for a year with cabergoline, there was no reduction in tumour size and serial perimetry showed gradual worsening of visual fields in both eyes. She was scheduled for TSS but was postponed.

She presented at 17 weeks of a spontaneous pregnancy with left eye discomfort and no other symptoms of raised intracranial pressure. MRI of the pituitary showed unchanged tumour size exhibiting mass effect with no evidence of apoplexy. Perimetry showed worsening of peripheral scotoma on the left eye with optic atrophy. Hormonal evaluation showed new onset central hypocortisolism. She underwent TSS at 19 weeks POA. Histopathology confirmed pituitary adenoma but stained negative for prolactin. Post-operatively, she developed central diabetes insipidus requiring regular desmopressin. There was no improvement in vision.

CONCLUSION
Pregnancy is a known risk factor for pituitary apoplexy. However, worsening of mass effect could be due to physiological changes of pregnancy resulting in pituitary enlargement. Surgery is recommended early prior to pregnancy especially in those with large non-functioning pituitary adenoma for optimal pregnancy outcomes. Patients who become pregnant require multidisciplinary care and TSS in the second trimester is an option. Hormonal deficiencies and cranial diabetes insipidus should be addressed promptly.