A 28-year-old woman with PCOS undergoes IVF with controlled ovarian hyperstimulation. On day 10 of stimulation her estradiol is 5,200 pg/mL and ultrasound shows 22 follicles ≥10 mm. She is at high risk for OHSS. The trigger shot used to reduce OHSS risk in an antagonist protocol while achieving final oocyte maturation is:

• A hCG 10,000 IU IM
• B GnRH agonist (buserelin 0.5 mg or leuprorelin 1 mg SC) ✓
• C Progesterone in oil IM
• D Recombinant LH 75 IU

Explanation

In a GnRH antagonist protocol, a GnRH agonist trigger (e.g., buserelin or leuprorelin SC) can be used instead of hCG to trigger final oocyte maturation. The agonist causes an endogenous LH/FSH surge sufficient for oocyte maturation but is rapidly cleared, resulting in early luteolysis and markedly reduced OHSS risk compared to hCG. This strategy is validated by multiple RCTs and is the recommended approach for high OHSS risk cycles in antagonist protocols, followed by a freeze-all strategy.

Reference: Shaw's Textbook of Gynaecology, 17th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.