A 24-year-old woman who is being treated for infertility with human menopausal gonadotropin came with complaints of sudden abdominal pain, nausea, vomiting, and breathlessness. The finding of the ultrasound is shown below. What is the most likely diagnosis?

Explanation

## Correct Answer: D. Ovarian hyperstimulation syndrome Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication of gonadotropin therapy used in infertility treatment. The patient's clinical presentation—sudden onset abdominal pain, nausea, vomiting, and breathlessness following human menopausal gonadotropin (hMG) administration—is pathognomonic for OHSS. The syndrome occurs due to exaggerated ovarian response to exogenous gonadotropins, leading to massive enlargement of both ovaries with multiple cysts (theca lutein cysts). This causes peritoneal irritation, third-spacing of fluid into the peritoneal cavity (ascites), and in severe cases, pleural effusion (explaining breathlessness). The ultrasound would show bilaterally enlarged ovaries with multiple cysts of varying sizes. OHSS is classified as mild (abdominal pain, mild distension, nausea) or severe (the above plus ascites, oliguria, hemoconcentration, electrolyte imbalance). Management is conservative in mild cases (rest, hydration, NSAIDs) and supportive in severe cases (IV fluids, electrolyte correction, monitoring for thrombosis). The condition is self-limiting, resolving within 7–10 days if pregnancy does not occur, or persisting longer if pregnancy is established. This is a well-recognized complication in Indian fertility clinics and requires vigilant monitoring during gonadotropin cycles. ## Why the other options are wrong **A. Polycystic ovarian syndrome** — PCOS is a chronic endocrine disorder characterized by anovulation and hyperandrogenism, not an acute complication of gonadotropin therapy. PCOS presents with irregular cycles, hirsutism, and infertility over months/years, not sudden abdominal pain and breathlessness within days of hMG injection. The acute presentation with ascites and bilateral ovarian enlargement is incompatible with PCOS. **B. Theca lutein cysts** — Theca lutein cysts are benign functional cysts that develop in response to elevated hCG (seen in pregnancy or molar pregnancy), not directly from gonadotropin stimulation alone. While theca lutein cysts ARE present in OHSS (they are the morphological finding), they are not the diagnosis—OHSS is the systemic syndrome caused by the exaggerated response. Naming only the cyst type misses the clinical syndrome of fluid shift and organ dysfunction. **C. Granulosa cell tumor** — Granulosa cell tumors are rare ovarian neoplasms that present insidiously with abdominal mass, ascites, or abnormal bleeding over weeks to months. They do not occur acutely following gonadotropin therapy. The acute onset (days after hMG) and bilateral ovarian involvement rule out a unilateral tumor. Granulosa cell tumors are not iatrogenic complications of fertility treatment. ## High-Yield Facts - **OHSS risk factors**: high estradiol levels (>3000 pg/mL), young age, low BMI, PCOS, previous OHSS, and high hCG post-ovulation trigger. - **Mild vs Severe OHSS**: Mild = abdominal pain + mild distension; Severe = ascites + oliguria + hemoconcentration + risk of thrombosis and renal failure. - **Theca lutein cysts** are the morphological hallmark of OHSS—multiple bilateral cysts visible on ultrasound, not a separate diagnosis. - **Management principle**: Conservative in mild OHSS (NSAIDs, hydration); supportive in severe (IV fluids, electrolyte monitoring, avoid NSAIDs if renal compromise). - **Resolution timeline**: Self-limiting in 7–10 days if no pregnancy; persists 4–6 weeks if pregnancy established (rising hCG perpetuates the syndrome). - **Indian context**: OHSS is increasingly common in Indian fertility centers due to rising demand for assisted reproduction and sometimes aggressive stimulation protocols. ## Mnemonics **OHSS Severity (CRASH)** **C**ramps (mild) → **R**enal (oliguria, creatinine rise) → **A**scites (fluid shift) → **S**evere (hemoconcentration, thrombosis) → **H**ospitalization needed. Helps grade severity from mild to life-threatening. **OHSS Trigger (HCGR)** **H**uman gonadotropins → **C**ycle stimulation → **G**igantic ovaries → **R**esponse syndrome. Mnemonic for the iatrogenic pathway. ## NBE Trap NBE may pair "theca lutein cysts" (the morphological finding) with OHSS to trap students who confuse the histological feature with the clinical diagnosis. The syndrome is OHSS, not the cysts themselves—students must recognize that cysts are a component, not the answer. ## Clinical Pearl In Indian fertility clinics, OHSS is a dreaded complication that can rapidly progress to life-threatening hypercoagulability and renal failure if not recognized early. Any infertility patient on gonadotropins presenting with acute abdominal pain and ascites should be assumed to have OHSS until proven otherwise—early fluid resuscitation and thromboprophylaxis can be lifesaving. _Reference: DC Dutta's Textbook of Obstetrics (7th ed.), Ch. 13 (Infertility); Harrison's Principles of Internal Medicine, Ch. 405 (Reproductive Endocrinology)_