Ovitrelle trigger shot: what it does, when it is given, and how to log it
Ovitrelle is one of the most talked-about medications in fertility treatment, mostly because of one thing: the clock. It is the injection that closes the stimulation phase and sets the timetable for retrieval or insemination. This page covers what the shot does, when it is usually given, the timeline that follows, and how to record the exact hour so nothing slips.
What the shot does
In a natural cycle the body releases a surge of LH that tells the mature follicle to release its egg. In treatment, instead of waiting for that surge, an external hormone mimics it: Ovitrelle contains choriogonadotropin alfa (recombinant hCG), which acts on the same receptor. The result is final egg maturation and the start of release — at a time your medical team chooses rather than a random one.
- • Given as a subcutaneous injection, usually in a pre-filled pen
- • Given once, at the end of stimulation, at a precise hour
- • Marks the end of the daily stimulation injections
- • Sets the timing of egg retrieval or insemination
The typical timeline
The table shows the general structure most clinics follow. Your exact times come from your treating team and may differ.
| Stage | Usually when | What to record |
|---|---|---|
| Final scan before the shot | Lead follicle around 17-22 mm | Follicle sizes, lining, E2 |
| Instruction from the clinic | Phone call the same day | Exact hour and dose given |
| Ovitrelle injection | Usually in the evening | The time you actually took it |
| Egg retrieval | About 34-36 hours after the shot | Arrival time and fasting rules |
| Ovulation (cycles without retrieval) | About 36-40 hours after the shot | Timed intercourse or IUI per instructions |
How to log the shot and not miss the hour
The instruction usually arrives by phone, somewhere between a scan, work and the rest of life, and the hour is said once. Move it straight into one fixed place, with a reminder.
- 1. Write the medication name, dose and time exactly as given.
- 2. Set an early reminder — for example 30-60 minutes before.
- 3. Mark it as taken, with the actual time, right after the injection.
- 4. Add the retrieval or insemination appointment next to the shot.
- 5. Keep the visit summary or form that carried the instruction.
Log Ovitrelle in Ovylia
In Ovylia you can add Ovitrelle to your medications with dose and time, get a phone reminder before it is due, and see the shot alongside your appointments and monitoring in the calendar — in English and Hebrew.
Add a medication and reminderFrequently asked questions
What is Ovitrelle and why is it given?
Ovitrelle is an injection containing choriogonadotropin alfa, a hormone that works like LH. It is given at the end of the stimulation phase as a "trigger shot" to complete egg maturation and start the release of the egg from the follicle, ahead of a natural cycle, IUI or egg retrieval.
When is the Ovitrelle shot given?
Your doctor sets the timing based on follicle monitoring — usually once the lead follicle reaches a suitable size (often around 17-22 mm) and hormone levels support it. The exact hour matters, which is why clinics give it as a specific instruction, for example "at 10pm".
How long after the Ovitrelle shot does ovulation happen?
Ovulation typically occurs about 36-40 hours after the injection, which is why egg retrieval is usually scheduled around 34-36 hours after it — just before ovulation. Your own schedule is always set by your clinic.
What if I am late or miss the time?
Even an hour's delay can shift ovulation and the planned retrieval or insemination. If you missed the time, are unsure the injection was given, or think the dose was wrong, contact your clinic as soon as possible instead of adjusting on your own.
Can Ovitrelle affect a pregnancy test?
Yes. Ovitrelle contains hCG — the same hormone a pregnancy test detects — so a home test taken too early can show a false positive. Your clinic will tell you when to take the beta hCG blood test.
Keep reading
The timing of the shot comes from your scans — the follicle monitoring guide explains what is measured at each visit. For the days after transfer, see after embryo transfer.
This page is general information and is not medical advice or a substitute for your care team's instructions. Dose, timing and sequence are decided by your treating doctor.