IS Case 580: Ovarian hyperstimulation syndrome

Nicholas Perry, MD

Imaging Sciences URMC

Imaging Sciences URMC 2010
Publication Date: 2011-11-17


Patient is a 38-year-old female on Clomid with abdominal pain.


CT of the pelvis (Fig. 1) demonstrates enlarged bilateral multicystic ovaries with large cysts and enhancing follicles. The left ovary measures 9 x 8 cm, the right is 7 x 8 cm and located posterior to the uterus. Surrounding free fluid is also present. Subsequent ultrasound images confirm CT findings (Figs. 2 & 3) showing large solid and cystic conglomerations defining enlarged ovaries bilaterally. The left ovary is shown to measure approximately 8 x 4 cm.


Ovarian hyperstimulation syndrome


Ovarian hyperstimulation syndrome (OHSS) is associated with infertility treatment using gonadotropin therapy or occasionally Clomiphene. These fertility agents induce follicular development increasing the chances of successful ovulation. In OHSS, the stimulation is too great resulting in multiple large luteinized cysts with significant ovarian enlargement. These changes are evident on sonography and CT with bilaterally enlarged multicystic ovaries and a normal uterus. Not surprisingly, the degree of ovarian enlargement increases the risk of serious complications including predisposition to ovarian torsion and rupture. A central distinguishing feature of this syndrome is the development of vascular hyperpermeability and subsequent fluid shifts causing ascites, pleural effusion, and other third-spacing. The differential diagnosis includes ovarian carcinoma and Meigs syndrome, but the clinical presentation is usually characteristic enough to exclude other possibilities. Ascites, ovarian enlargement, and symptoms will generally resolve in 1 to 2 weeks with conservative treatment and cessation of hormonal therapy.


  1. Bennett GL, Slywotzky CM, Giovanniello G. Gynecologic causes of acute pelvic pain: spectrum of CT findings. Radiographics. 2002 Jul-Aug;22(4):785-801. PMID: 12110710
  2. McArdle CR, Sacks BA. Ovarian hyperstimulation syndrome. AJR Am J Roentgenol. 1980 Oct;135(4):835-6. PMID: 6778122

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