Ovulation Trigger
Medication administered to induce final oocyte maturation and ovulation, typically hCG or GnRH agonist.
Full Definition
The ovulation trigger is a crucial component of ART protocols, administered when follicular development reaches optimal parameters to initiate final oocyte maturation and subsequent ovulation. Human chorionic gonadotropin (hCG) is the traditional trigger medication, mimicking the natural LH surge. GnRH agonist triggers are increasingly used, particularly in patients at high risk for ovarian hyperstimulation syndrome, as they provide more physiological stimulation. Timing is critical, with oocyte retrieval typically scheduled 34-36 hours post-trigger to capture oocytes at optimal maturity. The choice of trigger medication depends on stimulation protocol, OHSS risk factors, and whether fresh or frozen embryo transfer is planned.
Usage
Usage note: Hyphenate when used as compound adjective; may be used as two words when referring to the process.
In Context
- "The ovulation trigger was administered at 10 PM following confirmation of adequate follicular development." — Treatment cycle documentation
- "GnRH agonist trigger was selected to reduce OHSS risk in this high-responder patient." — Clinical decision rationale