Ovidrel and Trigger Shots

Ovidrel (choriogonadotropin alfa injection) is a fertility drug used to enhance and trigger ovulation. Ovidrel is a type of injectable medication that's also known as a "trigger shot." It may be used by itself or along with other fertility drugs. Ovidrel may be used in a cycle with timed sexual intercourse, intrauterine insemination (IUI), or in vitro fertilization (IVF) to improve the odds of pregnancy with each cycle.

Overview

Ovidrel is composed of recombinant human chorionic gonadotropin (r-hCG). Recombinant fertility drugs are made in a laboratory using DNA technology. They are molecularly similar to hormones made by the body. In the case of r-hCG, the lab-made hormone is similar to the body's natural luteinizing hormone (LH). LH is the hormone that triggers ovulation during the menstrual cycle.

woman giving herself a subcutaneous injection
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r-hCG and u-hCG Injections

Currently, there’s no generic version of recombinant human chorionic gonadotropin. However, the urinary extracted version of chorionic gonadotropin for injection (u-hCG), which is a similar fertility medication, is available in generic form. u-hCG is created by extracting and purifying hCG hormone from the urine of pregnant women. Brand names for u-hCG include Chorex, Novarel, Pregnyl, and Profasi.

While this article focuses on Ovidrel, much of the information can also be applied to urinary extracted chorionic gonadotropin.

Both forms of chorionic gonadotropin (r-hCG and u-hCG) are used in a similar way and offer comparable results, although some side effects may be slightly different.      

How Ovidrel Works

Ovidrel (injected r-hCG) acts very similar to the body's luteinizing hormone (LH) that spikes just before ovulation. The role of LH in the female reproductive system is to stimulate the maturing egg (still in its follicle in the ovary) to complete the stages of growth just before ovulation. Typically, there is a surge of LH about 36 hours before the follicle releases the egg.

Your body reacts to hCG the same way it does to LH.

When you inject Ovidrel (or any form of chorionic gonadotropin) into your body, as long as follicles in the ovary are at the right stage of maturation, hCG triggers the eggs to go through a final growth spurt and ovulate (be released from the follicles) within 36 hours.

This is why it’s sometimes called a "trigger shot" or "trigger injection."

When Ovidrel is used during a cycle with timed sexual intercourse or along with IUI, intercourse or the insemination procedure will be timed to occur just before the egg(s) ovulate, in order to maximize the odds for pregnancy.

When Ovidrel is used during an IVF cycle, your doctor doesn’t want the eggs to ovulate and leave the ovary on their own. Once the eggs ovulate, they can’t be retrieved for the IVF procedure. Instead, your doctor will schedule the egg retrieval for just before the expected ovulation time following the Ovidrel injection.

This is why it’s extremely important to follow your doctor’s directions on when to give yourself the Ovidrel injection as the timing is crucial down to the hour.

If you don’t or can’t give yourself the injection at the exact time your doctor prescribed, let your doctor’s office know right away.

When Ovidrel Is Used

Ovidrel may be used in a fertility treatment protocol for:

Ovidrel may be used alone, but it’s usually given along with other fertility drugs. For example:

  • It may be used along with the fertility drug Clomid.
  • It is frequently used along with gonadotropins (like Gonal-F or Follistim).
  • It is frequently used in an IUI cycle, with or without other fertility drugs.
  • It is almost always used during IVF treatment.

Unsubstantiated Use of Ovidrel for Weight Loss

Ovidrel and other forms of hCG have also been used in weight loss protocols, outside of the world of infertility and fertility treatments. There’s little to no evidence, however, that Ovidrel can help you lose weight.

When It's Not Used

Ovidrel is not recommended in women with primary ovarian insufficiency or those with very poor ovarian reserves. The medication (and fertility drugs in general) may not be effective for these women.

If you are at high risk of developing ovarian hyperstimulation syndrome (OHSS), your doctor may forgo Ovidrel. OHSS is one of the possible risks of fertility drug use. You may be at high risk for OHSS if:

  • You’ve experienced moderate to severe OHSS during previous fertility treatment cycles.
  • Your estrogen levels are very high before your scheduled Ovidrel shot.
  • Your ovaries have “overreacted” to the fertility drugs already given and produced “too many” follicles. (How much is too many will depend on your treatment protocol and your doctor’s opinion.)

Sometimes, your doctor will cancel your fertility treatment cycle mid-cycle based on the results of hormonal blood work and ultrasound monitoring of your ovaries. You might have the Ovidrel shot already at home, but be told not to use it.

If your doctor instructs you to not give yourself Ovidrel mid-cycle, it’s extremely important you follow these instructions. Going through with the injection could put your health at risk. Severe OHSS can be life-threatening.

If you’ve ever had an allergic reaction to Ovidrel or to other forms of injectable hCG, you also should not use the medication in future cycles.

Can You Use Ovidrel If You Have PCOS?

Women with polycystic ovarian syndrome (PCOS) may be at a higher risk of developing ovarian hyperstimulation syndrome (OHSS). However, this doesn’t necessarily mean you can’t use Ovidrel. In fact, Ovidrel is frequently used in fertility treatment cycles for women with PCOS. Talk to your doctor if you have concerns.

Timing and Administration

Exactly when you take Ovidrel will partially depend on whether it’s being used on its own, alongside Clomid, with gonadotropins, as part of an IUI cycle, or as part of an IVF cycle. However, the general usage of Ovidrel is similar regardless of the fertility treatment protocol.

Ovidrel is a liquid and it comes in a pre-filled, ready-to-inject device that’s relatively easy to use. Ovidrel is given as a subcutaneous injection. This means it’s injected into the fatty tissue just below the skin. (This is as opposed to intramuscular injection, like progesterone, that needs to be injected into the muscle.)

Always follow your doctor’s exact instructions for the day and time of day to give yourself the injection. Giving yourself the injection even just a few hours off from the prescribed time can cause problems for your treatment cycle.

What You'll Need

When you’re ready to give yourself the injection, make sure you have everything you need ready:

  • The Ovidrel prefilled syringe
  • The instructions (which you should read carefully first)
  • Alcohol swabs for medical use
  • Gauze
  • A container safe to dispose of the needle into

How to Give Yourself the Injection

Make sure the area you’re placing your supplies on is clean, dry, and flat, then follow these steps.

  1. Wash your hands in warm soapy water for at least 30 seconds. Dry them on a clean paper towel. If a friend or family member will be doing the injection for you, make sure they thoroughly wash their hands.
  2. Carefully remove an Ovidrel pre-filled syringe from the box.
  3. Aiming the needle upward, remove the safety cap covering the needle.
  4. While still pointing the needle upward, remove any air bubbles trapped in the syringe by gently tapping the side.
  5. Carefully push the plunger on the needle pushing the excess air up and out, until just a tiny droplet of medication appears at the tip of the needle.
  6. Choose the spot you’ll inject the medication; it should be an area on the abdomen and near the belly button, but at least one inch away from the belly button itself.
  7. Use one of the alcohol swabs to disinfect the chosen injection site.
  8. Let the area air-dry. Don’t blow on it to make it dry faster—this would blow germs back onto the area you just cleaned.
  9. Take the Ovidrel needle into one hand with a finger on the plunger and your other fingers on the canister. With your other hand, pinch the skin of your chosen injection site. Your goal is to create a generous fold of fatty tissue to inject the needle into.
  10. Insert the full needle into the pinched area at an angle of about 45 to 90 degrees.
  11. Once the needle is in, let go of the pinched skin. Now, slowly and carefully push the plunger on the Ovidrel syringe until all the medication is dispensed.
  12. Once all the medication is given, gently remove the needle from your belly. Use a gauze pad to apply gentle pressure to the site of injection. Any bleeding shouldn’t last long.

Place the used Ovidrel syringe into an approved sharps container. Don’t place it in your regular trashcan as it could be a threat to the safety of others. Talk to your fertility clinic’s nurse or doctor about how you should dispose of your needles in your state or country. Laws regulating what’s legal and what’s not for needle disposal vary by locality.

Note: If your doctor prescribed u-hCG, instead of Ovidrel’s r-hCG, you may need to prepare the needle for injections yourself. Your fertility clinic will provide instructions on what to do. If you’re unsure, don’t be afraid to call and ask.

Risks and Possible Side Effects

Most women do not experience any significant side effects beyond local discomfort at the injection point. In clinical trials of Ovidrel, one in three women using the medication for IVF treatment experienced at least one adverse effect. For those using it for ovulation stimulation only (like with an IUI cycle), one in four women experienced at least one adverse effect.

Some of the more common adverse effects of Ovidrel include:

  • Injection site pain or bruising
  • Upset stomach
  • Abdominal pain
  • Nausea
  • Vomiting 

Whenever fertility drugs are used, there is a risk of developing ovarian hyperstimulation syndrome (OHSS). OHSS is more often related to the use of gonadotropins along with Ovidrel, than from taking Ovidrel by itself.

Still, you should be aware of the possible symptoms. Talk to your doctor if you experience OHSS symptoms or have any questions.

Ovulation and Pregnancy

Ovulation typically occurs within 24 to 36 hours of an Ovidrel injection. If you’re having timed sexual intercourse with an Ovidrel shot, your doctor will likely recommend you have sex the night of the injection and every night after for two to three days.

If you’ve planned an IUI or IVF cycle, your doctor will give you instructions on when to come into the office. The optimal time is based on when you gave yourself the trigger shot.

Will Ovidrel Help You Get Pregnant?

Giving the odds of pregnancy success for those using Ovidrel is tricky because success depends on so many factors. For example, if you have a 28-year old IVF patient with a good prognosis using Ovidrel and compare her to a 41-year-old woman having an IUI cycle using Ovidrel, the success rates will vary significantly.

One study published in 2017 looked at whether an r-hCG shot (Ovidrel) improved IUI pregnancy success rates when compared to cycles where they relied on the natural LH surge, used r-hCG, or timed the injection to occur at the same time as the natural LH surge.

The researchers found a significant improvement in pregnancy success for cycles that used r-hCG and especially, those that combined an r-hCG injection with the body's LH surge.

The clinical pregnancy rate per cycle was:

  • 18% overall
  • 18.2% for those that received an r-hCG shot
  • Only 5.8% for cycles with no r-hCG shot
  • 30.7% for those who received the trigger shot at the same time as their body’s natural LH surge

Most studies do not find a difference in pregnancy success rates when comparing r-hCG (like Ovidrel) and u-hCG (urinary extracted hCG).

When to Take a Pregnancy Test

Ovidrel is molecularly similar to the hormone hCG, which is the pregnancy hormone that pregnancy tests detect in the urine. This means that if you take a pregnancy test soon after your trigger shot, you may get a positive result—even though you’re likely not pregnant (yet).

Ideally, you should not take a pregnancy test until 14 days after your trigger shot. This is the best timing for a pregnancy test with or without having used Ovidrel as taking a pregnancy test too early can lead to false negatives.

Cost

Your cost for Ovidrel will partially depend on whether you have insurance coverage for fertility treatments and which pharmacy you purchase the drug from.

Generally speaking, Ovidrel costs between $100 and $200.

Ovidrel vs. Pregnyl

Sometimes people refer to Pregnyl as the “generic” version of Ovidrel, but this isn’t technically correct. Pregnyl is a brand name of urinary extracted hCG (u-hCG).

A Cochrane Database study compared possible adverse effects and clinical pregnancy success rates between Ovidrel and Pregnyl. The study included 18 random control trials, involving almost 3,000 participants. The researchers concluded that there was no evidence that live birth rates, ongoing pregnancy rates, or the rate of developing OHSS was significantly different between the two medications.

A Word From Verywell

Navigating the world of trigger shots, particularly knowing if and when to include fertility medications (and which ones) into your journey toward pregnancy can be confusing and stressful. Your doctor will be the best resource to decide which fertility medications and treatments will be most effective for you.

In many cases, these medications, including Ovidrel, can greatly improve your shot at making a baby—and once you get the hang of the injections and optimal timing, the process may feel less daunting.

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Article Sources
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