The trigger shot is a fundamental step in many fertility treatments, including In Vitro Fertilization (IVF) and Intrauterine Insemination (IUI). This injection contains a hormone, often human chorionic gonadotropin (hCG), which mimics the body’s natural Luteinizing Hormone (LH) surge. Its purpose is to induce the final maturation of the eggs, preparing them for either ovulation or retrieval. The effectiveness of the entire cycle hinges on the precise timing and accurate technique of this self-administered injection.
Preparing for the Injection
The preparation phase begins with confirming the exact time provided by the fertility clinic. The timing of the shot is calculated to occur approximately 36 hours before an egg retrieval procedure. Administering the medication even slightly too early or too late can negatively affect egg maturity or cause premature ovulation. Setting multiple alarms and gathering all necessary supplies 15 to 30 minutes before the designated time helps reduce stress and rushing.
Proper storage and handling ensure the medication’s effectiveness. If the medication is a powdered form, such as Pregnyl or Novarel, it must be carefully mixed with a sterile diluent, following the exact instructions and dosage specified by your physician. Pre-filled syringe medications, like Ovidrel, should be removed from the refrigerator about 30 minutes before use to reach room temperature, which minimizes injection discomfort.
A clean, dry workspace is necessary for organizing supplies, including alcohol swabs, sterile needles, syringes, medication vials, and a sharps disposal container. Before uncapping the needle, double-check the medication’s expiration date and the dosage against the clinic’s instructions. Washing your hands thoroughly before handling any supplies helps prevent the introduction of bacteria to the injection site.
Locating the Proper Injection Site
The injection location is determined by the prescribed delivery method, which is most often a subcutaneous (SC) injection into the fatty layer just beneath the skin. The preferred site for subcutaneous fertility injections is the lower abdomen, specifically the area below the navel and above the pubic bone. Select a spot at least one to two inches away from the belly button to avoid dense tissue and nerves.
An alternate subcutaneous site is the front or outer part of the thigh, useful if the abdomen is tender from other daily injections. For repeated injections, rotate the exact spot within the designated area to prevent localized skin irritation, bruising, or the formation of hard lumps. Never inject into an area that is already bruised, swollen, or scarred.
Intramuscular Injection Sites
Some protocols or higher-volume medications may require an intramuscular (IM) injection, which delivers the medication deeper into the muscle tissue. The most common site for a self-administered IM injection is the upper outer quadrant of the buttock, or gluteal muscle. This location is chosen because it contains fewer major nerves and blood vessels than other muscle sites. Confirm with your fertility nurse whether your trigger shot is to be administered subcutaneously or intramuscularly, as the location and needle size differ significantly.
Step-by-Step Administration Guide
Once the medication is prepared, cleanse the chosen site thoroughly with an alcohol swab. Wipe the area in a circular motion, moving outward from the center, and allow the alcohol to completely air-dry to prevent a stinging sensation. For a subcutaneous injection, gently pinch a one- to two-inch fold of skin and fat with your non-dominant hand.
This pinching motion lifts the fatty tissue away from the underlying muscle, ensuring the medication is deposited correctly into the subcutaneous layer. Hold the syringe like a dart in your dominant hand, removing the protective cap from the needle. Insert the needle quickly and confidently into the pinched skin at an angle between 45 and 90 degrees, depending on the needle length and the amount of fatty tissue present.
After the needle is fully inserted, release the pinched skin. Slowly depress the plunger with firm, steady pressure until all the medication has been injected. Injecting the liquid at a slow and controlled pace is important, as rapid injection can increase discomfort and localized irritation.
Once the plunger reaches the end, pause for a few seconds to ensure the full dose has been delivered before withdrawing the needle. Withdraw the needle smoothly at the same angle it was inserted, and immediately apply gentle pressure to the injection site with a clean gauze pad or cotton ball. Avoid rubbing the area vigorously, as this can cause the medication to leak out or increase the likelihood of bruising.
Immediate Post-Injection Care
The first step following the injection is to dispose of the used needle and syringe immediately and safely into a designated sharps container. This puncture-proof plastic box protects against accidental needle sticks. Never attempt to recap a used needle or throw it into regular household trash.
It is common to experience localized side effects, such as mild redness, temporary bruising, or slight soreness at the injection site. These minor reactions are normal and usually resolve within a day or two. If there is a small amount of bleeding after removing the needle, continue to apply gentle pressure with a clean gauze pad until it stops.
Contact your fertility clinic immediately if you notice signs of a severe allergic reaction, such as difficulty breathing, swelling of the face or throat, or a widespread rash. Be aware of symptoms that could indicate Ovarian Hyperstimulation Syndrome (OHSS), including sudden, significant abdominal pain, severe bloating, rapid weight gain, or decreased urination. Prompt communication with your medical team ensures that any unexpected reactions are addressed quickly.