Egg retrieval is a significant step in fertility treatments, particularly in vitro fertilization (IVF), where mature eggs are collected from the ovaries. This procedure is carefully timed to maximize success. The “trigger shot” is a final medication administered to prepare the eggs for collection, ensuring they reach optimal maturity before retrieval.
Key Timing for Retrieval
The timing for egg retrieval after the trigger shot is precisely calculated. Retrieval is typically scheduled between 34 to 36 hours after the trigger shot is administered. This specific window is designed to collect the eggs just before natural ovulation, ensuring they are fully mature but still within the follicles.
Adhering to this schedule is important for optimal outcomes. If the trigger shot is administered too early, eggs may not reach full maturity, making them less viable for fertilization. Conversely, if the shot is given too late, or retrieval is delayed, there is a risk of spontaneous ovulation. While the 34-36 hour timeframe is standard, slight variations may exist based on individual patient responses and specific clinic protocols.
How the Trigger Shot Works
The trigger shot functions by mimicking the body’s natural luteinizing hormone (LH) surge, which initiates the final maturation of eggs and their release from ovarian follicles. During an IVF cycle, fertility medications stimulate the ovaries to produce multiple eggs. The trigger shot is the last injection given to prompt these eggs to complete their maturation process, preparing them for retrieval.
Common types of trigger medications include human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) agonists. hCG directly mimics the LH surge, while GnRH agonists stimulate the body to produce its own LH surge. Some protocols may even use a combination of both for a “dual trigger.” This final maturation process involves the eggs undergoing meiosis, a cell division process that prepares them for fertilization. The trigger shot also helps detach the eggs from the follicle walls, allowing for easier aspiration during retrieval.
Steps Before Retrieval
After receiving the trigger shot, patients must follow specific instructions to prepare for the egg retrieval procedure. Fasting, meaning no food or drink, typically after midnight the night before, is required due to the sedation administered during retrieval and helps prevent complications like vomiting.
Patients are also advised to avoid certain medications and supplements in the days leading up to the procedure. It is important to arrange for transportation, as patients will not be able to drive themselves home after the procedure due to the effects of sedation. Clinics often provide detailed instructions regarding these preparations for a safe and successful retrieval.
The Retrieval Procedure and Immediate Aftermath
The egg retrieval procedure is a minimally invasive process performed under light sedation or anesthesia. A physician uses ultrasound guidance to navigate a thin needle, usually inserted through the vaginal wall, into each ovarian follicle. The fluid containing the eggs is then aspirated and collected in test tubes. The procedure typically lasts between 15 to 30 minutes.
Immediately following the retrieval, patients are moved to a recovery area and monitored as the sedation wears off. Mild cramping, bloating, and abdominal discomfort are common sensations due to the ovaries being swollen and the aspiration process. Light spotting or bleeding may also occur. Patients are advised to rest for the remainder of the day and avoid strenuous activities for a few days to allow their bodies to recover. Information regarding the number of eggs retrieved is provided after the procedure.