Learn more about using Ovidrel trigger shots for fertility treatments, including possible side effects and success rates..
Types of Trigger Shots
There are several types of trigger shots available, including Ovidrel (r-hCG) and Pregnyl (u-hCG). Your doctor will determine which one is best for you.
Ovidrel (r-hCG)
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. 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.
Pregnyl (u-hCG)
While people sometimes refer to Pregnyl as the “generic” version of Ovidrel, this isn’t technically correct. Pregnyl is a brand name for 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 ovarian hyperstimulation syndrome (OHSS) (a potential complication of the medication) was significantly different between the two medications. Pregnyl is made from urinary-extracted chorionic gonadotropin (u-hCG). It is created by extracting and purifying hCG hormone from the urine of pregnant people. 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.
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. This is why it’s sometimes called a “trigger shot” or “trigger injection.”
Uses for Orvidrel
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. Ovidrel may be used in a fertility treatment protocol for a variety of reasons including for people with ovulatory infertility and in cases of unexplained infertility. It’s usually given along with other fertility drugs including Clomid and/or gonadotropins (like Gonal-F or Follistim). In some cases, Ovidrel is also used as part of an IVF treatment cycle, regardless of the cause of infertility. It is also frequently used in an IUI cycle, with or without other fertility drugs.
When It’s Not Used
Ovidrel is not recommended in people with primary ovarian insufficiency or those with very poor ovarian reserves. The medication (and fertility drugs in general) may not be effective for these people. If you are at high risk of developing ovarian hyperstimulation syndrome, 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. In this case, you might have the Ovidrel shot already at home, but be told not to use it. 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.
Ovidrel and PCOS
People 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 people with PCOS. Talk to your doctor if you have concerns.
Ovidrel and 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. However, this is not recommended. There’s little to no evidence that Ovidrel can help you lose weight.
Timing Your Ovidrel Shot
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.
How to Inject Ovidrel
When you’re ready to give yourself the injection, make sure you have everything you need ready:
A container to safely dispose of the needle after useAlcohol swabs for medical useClean gauzeThe instructions (which you should read carefully first)The Ovidrel prefilled syringe
Make sure the area you’re placing your supplies on is clean, dry, and flat, then follow these steps. 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.
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.
Ovidrel Side Effects and Risks
Most people who take Ovidrel do not experience any significant side effects beyond local discomfort at the injection point. In clinical trials of Ovidrel, one in three people using the medication for IVF treatment experienced at least one side 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 abdominal pain, upset stomach, nausea, vomiting, and pain or bruising at the site of injection. Whenever fertility drugs are used, there is a risk of developing ovarian hyperstimulation syndrome. Developing OHSS is more often related to the use of gonadotropins along with Ovidrel, than to taking Ovidrel by itself. Still, you should be aware of the risks and possible symptoms. Talk to your doctor if you experience OHSS symptoms or have any questions.
Ovidrel Success Rates
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. 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 them to a 41-year-old person 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% overall18.2% for those that received an r-hCG shotOnly 5.8% for cycles with no r-hCG shot30.7% 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).
Costs
Your cost for Ovidrel will partially depend on whether you have insurance coverage for fertility treatments and which pharmacy you purchase the drug from.
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 healthcare provider 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.
