A 29-year-old woman undergoing IVF with a GnRH antagonist protocol develops 25 follicles over 11 mm with estradiol above 4000 pg/mL on day 9 of stimulation. To minimise the risk of ovarian hyperstimulation syndrome, the MOST appropriate final maturation trigger is:

• A Urinary hCG 10,000 IU intramuscularly
• B Recombinant hCG 250 microgram subcutaneously
• C Progesterone 200 mg intramuscularly
• D GnRH agonist 0.2 mg subcutaneously ✓

Explanation

In an antagonist protocol, a GnRH agonist trigger produces a short endogenous LH and FSH surge that matures the oocytes while inducing luteolysis of the corpora lutea, sharply reducing late-onset OHSS compared with hCG triggers, whose long half-life sustains luteal activity. This benefit applies only under antagonist downregulation, which is why the protocol matters. Because luteal function is compromised, fresh embryo transfer is usually deferred and oocytes are frozen.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.