Endocrine Abstracts

Gonadotroph adenomas are usually detected by their local mass effects. Spontaneous ovarian hyperstimulation syndrome (OHS) has rarely been described as the main manifestation of gonadotroph adenomas in young women. We present a case with a prolonged OHS occurring during IVF ovarian induction leading to the discovery of a FSH pituitary tumour.

Case report: A 36 year-old, normal weight woman with 2 years primary infertility linked to oligomenorrhea and anovulation was included in an IVF program. PRL, androgens and gonadotrophins evaluation before ovulation induction was normal. She had presented a few weeks before a mild OHS after a five days single tablet of clomifene citrate. Before IVF induction, FSH and LH levels were 5 and 3 UI/l. Daily Decapeptyl treatment was started on January 7th for 12 days. Then long-acting Decapeptyl 3 mg was injected on January 18th after hormonal control. E2 level was very high (7300 ng/l) and enlarged ovaries were discovered with transvaginal u.s.: right 87×60 mm and left 69×50 mm with follicles and cysts (15–35 mm). Two days later, pelvic pain and more enlarged ovaries were treated with puncture but cysts quickly reappeared. One month after long-acting GnRH analog injection, E2 and inhibin B were elevated (2300 ng/l and 343 ng/l) and FSH and LH still detectable: 3 and 1.1 UI/l. Since OHS persisted, a gonadotroph adenoma was suspected. A 10 mm adenoma was found in the right part of the pituitary with MRI. Before surgery, FSH and αSU were elevated with no response after GnRH test, in contrast to LH which increased. At the end of March, the surgeon removed a right microadenoma and the pathologist confirmed a gonadotroph adenoma: all cells stained for βFSH and 5% reacted with anti- αSU and anti-βLH antisera. Shortly after surgery, hormone levels normalized and an ovulatory cycle was observed but ovarian size was persistently increased (30 mm cysts) 4 months after initial stimulation.

Conclusion: This case is unusual: OHS observed during an IVF program persisted and elevated FSH after GnRH long-acting analog allowed discovering a FSH pituitary adenoma cured by surgery. Enlarged ovaries were still detected 4 months after initial ovulation induction.