OHSS and fertility-treatment complications — Golan grading, VEGF pathophysiology, prophylaxis (cabergoline, GnRH antagonist trigger), and ICU management

Also known as Ovarian hyperstimulation syndrome · OHSS · Fertility treatment complications · Severe OHSS · Critical OHSS · GnRH agonist trigger

Exam-exhaustive FRANZCOG fellowship topic on ovarian hyperstimulation syndrome and fertility-treatment complications. Anchored to the RANZCOG CREI consensus (2015), the ASRM Practice Committee opinion, and the ESHRE ovarian-stimulation guideline. Covers the Golan classification (mild / moderate / severe / critical, with reproductive endocrinology modification), the VEGF-mediated capillary-leak pathophysiology, the recognition (ovarian size, haematocrit, oliguria, ascites), the prophylaxis ladder (GnRH antagonist protocol with agonist trigger, prophylactic cabergoline 0.5 mg daily, low-dose hCG trigger, freeze-all), the supportive management (crystalloid then colloid, paracentesis, thromboprophylaxis, ICU for severe and critical disease), the long-term implications for ovarian function, and the rare but life-threatening complications (thromboembolism, ARDS, torsion). Globally defensible at MRCOG Part 2/3 and ABOG level.

high14 referencesUpdated 28 July 202615 min readVerification in progress

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10 MCQs

One-line fellowship answer

OHSS is an iatrogenic, VEGF-mediated capillary-leak syndrome triggered by hCG acting on multiple corpora lutea in stimulated IVF cycles. The Golan classification (with reproductive endocrinology modification) grades it mild (Grade 1 distension, Grade 2 nausea and ovaries 5 to 12 cm), moderate (Grade 3 ascites on ultrasound), severe (clinical ascites or hydrothorax, oliguria under 500 mL per 24 hours, haematocrit over 0.45, ovaries over 12 cm), or critical (anuria, ARDS, thromboembolism, haematocrit over 0.55, severe leucocytosis). Prophylaxis is the high-yield answer: in at-risk women (PCOS, AMH over 35 pmol/L, antral follicle count over 24, prior OHSS), use a GnRH antagonist protocol with a GnRH agonist trigger (the most effective single intervention — drives severe OHSS to near zero when combined with freeze-all), or prophylactic cabergoline 0.5 mg daily orally for 5 to 8 days from hCG trigger (dopamine agonist halves moderate-to-severe OHSS). Treatment once severe is supportive: admit, crystalloid then colloid, thromboprophylaxis with LMWH, paracentesis for tense ascites (the most effective single intervention in established disease), and ICU for critical disease. Long-term ovarian function is preserved.^[1]^[2]^[6]^[14]

It is Sunday morning at 06:40 and the IVF coordinator calls you from the day unit. A 31-year-old woman with PCOS is day 6 post-oocyte pickup after an antagonist cycle with 28 oocytes retrieved. Her trigger was hCG 5000 IU because the couple wanted a fresh transfer. She has gained 3.5 kg in 36 hours, is vomiting, and has not passed urine since midnight. Her abdomen is distended and tympanitic, her heart rate is 118 bpm, her blood pressure is 96/58 mmHg, and her haematocrit (drawn on arrival) is 0.49. She has booked a frozen embryo transfer but you can see the dilemma building. Your job is to recognise this as severe OHSS before it progresses to critical, escalate to admission and supportive care, and — separately — debrief the stimulation team about agonist trigger and prophylactic cabergoline for the next cycle.^[1]^[2]^[14]

References14Show

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