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Trigger Shots in IVF: Purpose, Timing & What to Know

If you're preparing for IVF, you’ve probably heard about the “trigger shot.” It’s a key milestone in your cycle and plays an essential role in helping your eggs mature at exactly the right time. Here’s what you can expect and why timing matters so much.

What Is a Trigger Shot?

The trigger shot is an injection — often containing hCG or a medication called Lupron — that tells your body it’s time to mature the eggs in your follicles. In a natural cycle, your brain does this automatically. During IVF, we use a trigger shot so we can time egg retrieval with precision.

Why the Trigger Shot Matters

The trigger helps:

• Complete the final stage of egg maturation

• Ensure eggs are ready for retrieval

• Reduce the risk of immature eggs

• Improve embryo development

Your provider will select the type of trigger best suited for your hormone levels and risk factors, including ovarian hyperstimulation syndrome (OHSS).

Timing Is Everything

One of the most important parts of IVF is giving the trigger shot exactly when instructed — usually 34–36 hours before egg retrieval.

Giving it too early or too late can affect the maturity of the eggs, which is why your care team gives you very specific timing.

Types of Trigger Shots

Your doctor may recommend:

• hCG trigger (traditional trigger)

• Lupron trigger (for patients at risk of OHSS)

• Dual trigger (a combination of hCG + Lupron)

Each option is selected based on your hormones, follicle growth, and overall treatment plan.

What to Expect When Taking the Trigger

Most patients describe it as similar to other fertility injections. You may experience mild bloating or cramping afterward — that’s normal as the follicles finalize maturation.

Your team will walk you through exactly how to administer the shot and what to expect afterward.

Final Thoughts

The trigger shot is one of the final steps before egg retrieval — and an exciting milestone in your IVF journey. At RSCNJ, we ensure you feel fully prepared, supported, and confident as you reach this stage and beyond.

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