What is the Origin of IVF Trigger Shot?

The term is derived from the clinical protocol of 'In Vitro Fertilization' (IVF) and the action of the 'Trigger Shot'. The use of hCG to induce ovulation in fertility treatments dates back to the mid-20th century, becoming a standardized, pivotal step in controlled ovarian hyperstimulation protocols for IVF following the first successful procedures.

What is the Mechanism of IVF Trigger Shot?

The hCG-based trigger shot functions by binding to the Luteinizing Hormone (LH) receptors on the ovarian granulosa cells, acting as a powerful and sustained LH analog. This binding initiates a cascade of molecular events within the follicle, including the resumption of meiosis in the oocyte and the structural changes necessary for follicular rupture. When a GnRH agonist is used as the trigger, it causes a massive, short-lived release of endogenous LH and FSH from the pituitary, achieving the same final maturation and release effect without the prolonged receptor activation seen with hCG.

IVF Trigger Shot ∞ Area

IVF Trigger Shot

Meaning

The IVF Trigger Shot is a critical, precisely timed subcutaneous or intramuscular injection administered during an In Vitro Fertilization (IVF) cycle to induce the final maturation of ovarian follicles and prompt the release of eggs from the ovaries. This injection, typically containing human Chorionic Gonadotropin (hCG) or a Gonadotropin-Releasing Hormone (GnRH) agonist, mimics the natural Luteinizing Hormone (LH) surge that occurs mid-cycle. Proper timing of the trigger shot is absolutely essential, as it dictates the optimal window for subsequent egg retrieval.