Gonasi Set
Human Chorionic Gonadotropin (hCG) for Fertility Treatment
Quick Facts About Gonasi Set
Key Takeaways About Gonasi Set
- Triggers ovulation: Gonasi Set mimics the natural LH surge, causing mature follicles to release eggs – essential in IVF and ovulation induction cycles
- Requires medical supervision: Treatment must be supervised by a physician experienced in fertility treatment, with ultrasound monitoring to assess follicular development
- Risk of OHSS: Ovarian hyperstimulation syndrome is a potentially serious complication – seek immediate medical attention for sudden abdominal swelling, nausea, or difficulty breathing
- May cause false positive pregnancy tests: hCG can be detected in urine and blood for up to 10 days after injection, giving falsely positive pregnancy test results
- Prepare immediately before use: The powder must be dissolved in the provided solvent just before injection – the reconstituted solution cannot be stored
What Is Gonasi Set and What Is It Used For?
Gonasi Set contains highly purified human chorionic gonadotropin (hCG), a naturally occurring hormone that triggers the final maturation and release of eggs from the ovaries. It is used in fertility treatment to induce ovulation in women undergoing assisted reproductive technology (ART) or who have difficulty ovulating on their own.
Human chorionic gonadotropin (hCG) belongs to the family of gonadotropins, a group of hormones that play a central role in reproduction and fertility. In the natural menstrual cycle, the pituitary gland releases a surge of luteinising hormone (LH) approximately halfway through the cycle, which triggers ovulation – the release of a mature egg from a follicle in the ovary. Because hCG shares structural and functional similarities with LH, it can be used as an exogenous trigger to induce this same ovulatory process when administered at the right time.
Gonasi Set is manufactured by IBSA Farmaceutici Italia and is derived from the urine of pregnant women, where hCG is naturally produced in large quantities by the placenta. The active substance undergoes extensive purification to yield a highly purified product suitable for medical use. This urinary-derived hCG has been used in reproductive medicine for decades and remains an essential component of many fertility treatment protocols worldwide.
The two primary clinical indications for Gonasi Set are:
- Triggering final follicular maturation and ovulation in assisted reproductive technology (ART): In IVF (in vitro fertilisation) and other ART procedures, the ovaries are first stimulated with follicle-stimulating hormone (FSH) to grow multiple follicles, each containing an egg. Once the follicles have reached an adequate size (typically 17–20 mm as determined by ultrasound), Gonasi Set is administered to trigger the final maturation of the oocytes and their release from the follicles. Egg retrieval is then performed approximately 34–36 hours after the hCG injection.
- Ovulation induction in anovulatory or oligo-ovulatory women: In women who do not ovulate naturally (anovulation) or who produce eggs infrequently (oligo-ovulation), Gonasi Set can be used after follicular stimulation to trigger the release of the egg, enabling natural conception or intrauterine insemination (IUI).
Gonasi Set is marketed under different trade names across Europe: Gonasi Set (in Denmark, Finland, Norway, and Sweden), Gonasi Kit (in Slovakia and Spain), Gonasi (in the Netherlands), Gonadotrophine Chorionique IBSA (in France), and Zivafert (in Poland, Czech Republic, and Hungary). The strength and pharmaceutical form are identical in all countries.
What Should You Know Before Using Gonasi Set?
Before using Gonasi Set, your doctor will perform a thorough evaluation of your reproductive system and overall health. Gonasi Set is contraindicated in women with ovarian, uterine, or breast cancer, untreated endocrine disorders, or conditions making normal pregnancy impossible. Serious risks include ovarian hyperstimulation syndrome (OHSS) and blood clots.
Fertility treatment with gonadotropins is a complex medical process that requires careful patient selection, thorough monitoring, and experienced medical supervision. Before starting treatment with Gonasi Set, your doctor will assess your medical history, perform physical examinations, and conduct relevant investigations to ensure that this treatment is appropriate and safe for you.
Contraindications
You should not use Gonasi Set if any of the following conditions apply to you:
- Allergy to hCG or any excipient: If you are allergic to human chorionic gonadotropin or any of the other ingredients in Gonasi Set (listed in the contents section), you must not use this medicine
- Untreated endocrine disorders: Conditions involving the thyroid gland, pituitary gland, or adrenal glands that are not adequately treated – these can interfere with the hormonal pathways required for successful fertility treatment
- Hormone-dependent cancers: Cancer of the ovaries, uterus, or breast – hCG could potentially stimulate the growth of hormone-sensitive tumours
- Conditions making normal pregnancy impossible: Including premature ovarian failure, absent uterus, early menopause, blocked fallopian tubes (when not undergoing IVF), uterine fibroids, or other significant abnormalities of the reproductive organs
- Unexplained vaginal bleeding: Recent vaginal bleeding of unknown cause must be investigated before starting treatment
Warnings and Precautions
Talk to your doctor before using Gonasi Set if you have or have had any of the following conditions:
- Abnormalities of the reproductive organs – your doctor will check that your reproductive system is suitable for treatment
- Chronic diseases such as diabetes or cardiovascular disease – these may require additional monitoring during treatment
- Risk factors for blood clots (thrombosis): including obesity, personal or family history of blood clots, or recent immobility
- Previous OHSS – you may be at increased risk of developing ovarian hyperstimulation syndrome again
- Previous abdominal surgery – may increase the risk of complications during treatment
- Ovarian cysts – existing cysts not related to polycystic ovarian syndrome should be evaluated before starting treatment
Ovarian Hyperstimulation Syndrome (OHSS)
OHSS is a serious and potentially life-threatening medical condition that can occur during gonadotropin treatment, including with Gonasi Set. It develops when the ovaries become overstimulated, causing the growing follicles to become much larger than normal. This leads to fluid leaking from the ovarian blood vessels into the abdominal cavity and, in severe cases, into the chest.
Your doctor will perform regular ultrasound examinations of the ovaries and may check hormone levels in your blood to monitor the response to treatment and reduce the risk of OHSS. The European Society of Human Reproduction and Embryology (ESHRE) recommends careful cycle monitoring as the cornerstone of OHSS prevention.
- Severe abdominal pain or sudden abdominal swelling
- Nausea and vomiting
- Sudden weight gain due to fluid accumulation
- Diarrhoea
- Decreased urine output
- Difficulty breathing or shortness of breath
Blood Clots (Thrombosis)
The risk of developing blood clots increases during pregnancy, and this risk may be further elevated during IVF treatment, particularly in women with pre-existing risk factors. Blood clots can lead to serious and potentially life-threatening conditions, including:
- Pulmonary embolism (blood clot in the lungs)
- Stroke
- Heart attack
- Deep vein thrombosis (blood clot in the legs or arms)
- Reduced blood flow to vital organs, which may cause organ damage
If you have risk factors for blood clots (for example, if you are overweight, or if you or a family member has ever had a blood clot), inform your doctor before starting treatment. Your doctor may recommend preventive measures such as low-molecular-weight heparin during the treatment cycle.
Multiple Pregnancy and Pregnancy Complications
If treatment with Gonasi Set leads to pregnancy, there is an increased chance of having twins or a higher-order multiple pregnancy, especially when the medicine is combined with other ovulation-stimulating drugs such as human menopausal gonadotropin (hMG). Multiple pregnancies carry significantly increased health risks for both the mother and the babies, including premature birth, low birth weight, pre-eclampsia, and complications during delivery.
For women undergoing fertility treatment, there is also a slightly increased risk of miscarriage and ectopic pregnancy (a pregnancy that develops outside the uterus, usually in a fallopian tube). Your doctor will perform an early ultrasound examination to confirm that the pregnancy is developing normally and to rule out an ectopic pregnancy.
Pregnancy and Breastfeeding
Do not use Gonasi Set if you are already pregnant or breastfeeding. If you think you might be pregnant, consult your doctor before using this medicine. Gonasi Set is intended to be used specifically to achieve pregnancy, but once pregnancy has been confirmed, it should not be administered further unless specifically instructed by your fertility specialist.
False Positive Pregnancy Tests
Since pregnancy tests work by detecting hCG in your urine or blood, and Gonasi Set contains hCG, you may receive false positive pregnancy test results for up to 10 days after receiving the injection. Your fertility specialist will advise you on the appropriate timing for a pregnancy test to ensure accurate results.
Driving and Operating Machinery
Gonasi Set is not expected to affect your ability to drive or operate machinery. However, you should assess your own fitness to drive, as some patients may experience side effects such as headache, mood changes, or fatigue that could impair concentration. Discuss with your doctor if you are unsure.
Sodium Content
This medicine contains less than 1 mmol (23 mg) sodium per reconstituted solution, meaning it is essentially "sodium-free". This is relevant for patients on a controlled sodium diet.
How Does Gonasi Set Interact with Other Drugs?
Gonasi Set has relatively few known drug interactions compared to many other medicines. However, it is important to inform your doctor about all medications you are taking, particularly other ovulation-stimulating drugs and high-dose corticosteroids, as these can affect the response to treatment.
As a protein hormone, hCG is not metabolised by the liver cytochrome P450 enzyme system, which is responsible for most drug–drug interactions. This means that conventional pharmacokinetic interactions are unlikely. However, certain pharmacodynamic interactions (where other drugs affect the clinical outcome of treatment) are clinically relevant and should be considered.
Clinically Relevant Interactions
| Drug | Category | Effect | Recommendation |
|---|---|---|---|
| Human menopausal gonadotropin (hMG) | Fertility hormone | Combined use increases ovarian stimulation, raising the risk of OHSS and multiple pregnancy | Careful ultrasound monitoring of follicular response is essential; dose adjustments may be needed |
| Recombinant FSH (follitropin alfa/beta) | Fertility hormone | Sequential use is standard in ART, but excessive stimulation increases OHSS risk | Monitor follicle count and oestradiol levels before administering hCG trigger |
| Corticosteroids (high dose) | Anti-inflammatory / Immunosuppressant | May interfere with hormonal pathways involved in ovulation and implantation | Inform your doctor; dose timing and adjustments may be required |
| GnRH agonists (e.g. leuprolide, buserelin) | Pituitary downregulation | Used sequentially in controlled ovarian stimulation protocols; timing is critical | Administered according to specific protocol; do not alter timing without medical advice |
| GnRH antagonists (e.g. cetrorelix, ganirelix) | Premature ovulation prevention | Used in flexible antagonist protocols to prevent premature LH surge before hCG trigger | Coordinated timing is essential; follow your fertility clinic’s protocol precisely |
Always tell your doctor about all medicines you are currently taking, including over-the-counter medicines, herbal remedies, and dietary supplements. While hCG has limited direct drug interactions, your overall medication profile is important for optimising treatment outcomes and ensuring safety during fertility treatment and any resulting pregnancy.
What Is the Correct Dosage of Gonasi Set?
The recommended dose of Gonasi Set is 5,000 IU or 10,000 IU, administered as a single injection 24–48 hours after optimal follicular stimulation has been achieved. The medicine is given by subcutaneous or intramuscular injection. Your fertility specialist will determine the exact dose and timing based on your individual treatment protocol.
Gonasi Set is supplied as a powder that must be reconstituted (dissolved) in the provided solvent immediately before injection. Each vial is for single use only and the solution must be used immediately after preparation. Always use Gonasi Set exactly as your doctor has instructed.
Assisted Reproductive Technology (IVF/ICSI)
Trigger Dose for Egg Retrieval
Standard dose: 5,000 IU or 10,000 IU as a single injection
Timing: Administered 24–48 hours after optimal follicular stimulation has been achieved, as determined by ultrasound and/or hormone monitoring
Egg retrieval: Typically scheduled approximately 34–36 hours after the hCG injection
The dose of 10,000 IU is achieved by using two vials of 5,000 IU reconstituted in the solvent from a single pre-filled syringe.
Ovulation Induction
Triggering Ovulation for Natural Conception or IUI
Standard dose: 5,000 IU or 10,000 IU as a single injection
Timing: Administered when the dominant follicle has reached adequate maturity (typically 17–22 mm), as confirmed by ultrasound
Ovulation usually occurs approximately 36–48 hours after the injection. Timed intercourse or intrauterine insemination is coordinated accordingly.
Children and Adolescents
Gonasi Set is not intended for use in children and adolescents. This medicine is indicated for adult women undergoing fertility treatment only.
How to Prepare and Administer the Injection
After receiving appropriate training from your healthcare professional, you may be able to prepare and administer subcutaneous injections of Gonasi Set at home. It is essential that your doctor or nurse has demonstrated the correct technique before your first self-injection. The following is a summary of the key steps:
- Wash your hands thoroughly and prepare a clean surface with the supplied materials: the vial of powder, the pre-filled syringe of solvent, the long needle (for reconstitution and intramuscular injection), and the short needle (for subcutaneous injection).
- Attach the long needle to the pre-filled syringe. Remove the cap from the vial and clean the rubber stopper with an alcohol swab.
- Inject the solvent through the rubber stopper into the vial containing the powder. Roll the vial gently between your hands until the powder is completely dissolved. Do not shake.
- Draw up the solution: With the needle still in the vial, turn it upside down and slowly draw all of the reconstituted solution into the syringe. If preparing 10,000 IU, transfer this first solution into a second vial and repeat the dissolution process.
- For subcutaneous injection: Replace the long needle with the short needle. Remove air bubbles by holding the syringe upright and tapping gently, then pushing the plunger until a small drop appears at the needle tip.
- Inject: Clean the injection site (lower abdomen below the navel, or thigh) with an alcohol swab. Pinch the skin firmly and insert the needle at a 45° or 90° angle. Inject slowly and steadily. Remove the needle quickly and apply gentle pressure to the site.
- Dispose of used materials safely in an appropriate sharps container. Never reuse needles or syringes.
The reconstituted solution must be clear and colourless. Do not use if it is cloudy, discoloured, or contains visible particles. Only use the solvent provided in the pack – do not substitute with other liquids.
Missed Dose
If you forget to administer Gonasi Set at the scheduled time, contact your fertility clinic immediately. The timing of the hCG trigger is critical in fertility treatment – even a few hours of delay can affect the outcome of egg retrieval or ovulation. Do not attempt to adjust the timing on your own.
Overdose
The effects of overdose with Gonasi Set are not well characterised, but it is expected that an excessive dose could trigger ovarian hyperstimulation syndrome (OHSS). Symptoms may include severe abdominal pain, nausea, vomiting, rapid weight gain, and difficulty breathing. Seek immediate medical attention if you suspect you have received too much of this medicine. Contact your local emergency services or poison control centre without delay.
Stopping Treatment
If you are considering stopping treatment with Gonasi Set or have concerns about continuing your fertility cycle, talk to your doctor before making any changes. Discontinuing treatment at certain points in the cycle may affect the outcome, and your doctor can advise you on the best course of action. If treatment needs to be stopped due to an excessive ovarian response, your doctor may withhold the hCG trigger to prevent the development of OHSS.
What Are the Side Effects of Gonasi Set?
The most significant potential side effect of Gonasi Set is ovarian hyperstimulation syndrome (OHSS), which ranges from mild (common, up to 1 in 10) to severe (uncommon to rare). Other common side effects include injection site reactions, swelling, headache, mood changes, and breast tenderness. Stop using Gonasi Set and seek immediate medical attention for symptoms of severe OHSS or allergic reactions.
Like all medicines, Gonasi Set can cause side effects, although not everybody gets them. The likelihood and severity of side effects depend on individual factors, the treatment protocol used, and the degree of ovarian response. Your fertility team will monitor you closely to detect and manage any adverse effects promptly.
- Severe abdominal pain with nausea, vomiting, and rapid weight gain (signs of severe OHSS)
- Sudden difficulty breathing or chest pain
- Swelling of the face, eyes, lips, tongue, or throat (signs of severe allergic reaction)
- Widespread skin rash, difficulty breathing, or wheezing
- Severe pain on one side of the lower abdomen (possible ovarian torsion or cyst rupture)
Common
May affect up to 1 in 10 people
- Mild to moderate ovarian hyperstimulation syndrome (OHSS): enlarged ovaries, ovarian cysts, abdominal pain with nausea and vomiting
- Injection site reactions: redness, bruising, swelling, itching, or pain at the injection site
- Swelling (oedema)
- Mood changes
- Headache
- Breast tenderness or pain
Uncommon
May affect up to 1 in 100 people
- Severe ovarian hyperstimulation syndrome: pelvic pain, nausea, vomiting, weight gain, fluid accumulation in the abdomen (ascites) or chest (pleural effusion)
- Agitation and restlessness
- Fatigue
Rare
May affect up to 1 in 1,000 people
- Rupture of ovarian cysts (a rare complication of severe OHSS)
- Blood clots (thromboembolic events) as a complication of OHSS: including deep vein thrombosis, pulmonary embolism, and stroke
- Severe allergic reactions (anaphylaxis): swelling of the face, tongue, or throat, difficulty breathing, skin rash
- Angioedema (swelling of deeper skin layers), often with urticaria (hives)
- Widespread skin rash
Understanding and Managing OHSS
OHSS typically develops within the first week after hCG administration, although late-onset OHSS can occur in conjunction with early pregnancy. Mild OHSS is relatively common during stimulated fertility cycles and usually resolves on its own with conservative management (rest, adequate fluid intake, monitoring). Moderate and severe OHSS require closer medical supervision and may necessitate hospitalisation.
The ESHRE has published detailed guidelines on the prevention and management of OHSS. Key preventive strategies include using the lowest effective hCG dose, considering a GnRH agonist trigger instead of hCG in high-risk patients, and withholding the hCG trigger altogether if an excessive number of follicles develop (a strategy known as "cycle cancellation" or "coasting").
Ovarian Torsion
Ovarian torsion (twisting of the ovary) is a rare but serious complication that can occur when the ovaries are enlarged following gonadotropin stimulation. If an ovary twists, the blood supply can be cut off, which constitutes a medical emergency requiring immediate surgical intervention. Symptoms include sudden, severe one-sided lower abdominal pain, nausea, and vomiting. Contact your doctor or go to an emergency department immediately if you experience these symptoms.
If you experience any side effects not listed here, or if any side effect becomes severe or persistent, contact your doctor or fertility clinic. Reporting suspected side effects contributes to the ongoing monitoring of the medicine's benefit-risk balance.
How Should You Store Gonasi Set?
Store Gonasi Set at or below 25°C (77°F) in the original carton to protect from light. The reconstituted solution must be used immediately after preparation – it cannot be stored. Keep out of the sight and reach of children.
Store the vial of powder and the pre-filled syringe of solvent in their original packaging to protect them from light. Do not store above 25°C. Do not freeze. Keep the medicine out of the sight and reach of children at all times.
Check the expiry date printed on the outer carton, the vial, and the pre-filled syringe before use (marked "EXP"). If the expiry date is expressed as month/year, the expiry date is the last day of the stated month. Do not use Gonasi Set after this date.
Once the powder has been dissolved in the solvent, the solution must be used immediately. The reconstituted solution must be clear and colourless. Do not use if the solution appears cloudy or contains visible particles.
Do not dispose of medicines via wastewater or household waste. Ask your pharmacist how to safely dispose of medicines that are no longer needed. These measures help protect the environment from pharmaceutical contamination.
What Does Gonasi Set Contain?
Each vial of Gonasi Set contains 5,000 IU of highly purified human chorionic gonadotropin as a freeze-dried powder. The powder is reconstituted using the provided pre-filled syringe containing 1 ml of sodium chloride 9 mg/ml solution. Lactose monohydrate is the only excipient in the powder.
Active Ingredient
The active substance is human chorionic gonadotropin (hCG), derived from the urine of pregnant women. Each vial contains 5,000 International Units (IU) of highly purified hCG. The protein is produced naturally by the placenta during pregnancy and undergoes extensive purification for pharmaceutical use.
Inactive Ingredients (Excipients)
Vial (powder): Lactose monohydrate is the only excipient in the freeze-dried powder, serving as a stabiliser and bulking agent.
Pre-filled syringe (solvent): The solvent is a sterile sodium chloride 9 mg/ml solution (0.9% saline) containing water for injections and sodium chloride.
Appearance and Packaging
Powder: White to almost white, freeze-dried powder in a type I glass vial, sealed with a rubber stopper and flip-off aluminium cap.
Solvent: Clear and colourless solution in a 1 ml pre-filled syringe (type I glass).
A single pack contains: one vial of powder, one pre-filled syringe of solvent, one long needle (for reconstitution and intramuscular injection), and one short needle (for subcutaneous injection). A multipack containing 10 single packs is also available. Not all pack sizes may be marketed in all countries.
Marketing Authorisation Holder and Manufacturer
Gonasi Set is manufactured and distributed by IBSA Farmaceutici Italia srl, Via Martiri di Cefalonia 2, 26900 Lodi, Italy. It is approved throughout the European Economic Area under various trade names including Gonasi Set, Gonasi Kit, Gonasi, Gonadotrophine Chorionique IBSA, and Zivafert.
How Does Gonasi Set Work in the Body?
Gonasi Set works by mimicking the action of luteinising hormone (LH). When administered at the right point in a stimulated cycle, hCG binds to LH/hCG receptors on ovarian follicular cells, triggering the final maturation of oocytes and ovulation approximately 36–48 hours later.
Human chorionic gonadotropin (hCG) is a glycoprotein hormone consisting of two subunits: an alpha subunit (which is identical to that of LH, FSH, and thyroid-stimulating hormone) and a unique beta subunit that confers its specific biological activity. The alpha subunit allows hCG to bind to the LH/hCG receptor, while the beta subunit determines its specificity and longer half-life compared to LH.
In the natural menstrual cycle, a surge of LH from the pituitary gland triggers the final stages of oocyte maturation within the follicle, the resumption of meiosis (the final cell division that produces a mature egg), and ultimately the rupture of the follicle and release of the egg (ovulation). Because hCG has a very similar molecular structure and binds to the same receptor as LH, an injection of hCG can effectively replicate this LH surge when administered exogenously.
The key advantage of using hCG rather than relying on endogenous LH is precise timing. In IVF treatment, the exact moment of egg retrieval is critically important – the eggs must be collected after they have undergone final maturation but before spontaneous ovulation occurs. By controlling the trigger with an hCG injection, fertility specialists can schedule egg retrieval with a high degree of precision, typically 34–36 hours after administration.
Pharmacokinetic Profile
After intramuscular injection, hCG is absorbed relatively slowly, with peak serum levels typically reached within 6–16 hours. After subcutaneous injection, absorption is somewhat slower but bioavailability is comparable. The elimination half-life of urinary-derived hCG is approximately 33 hours, which is significantly longer than that of endogenous LH (approximately 60 minutes). This prolonged half-life provides sustained stimulation of the LH/hCG receptor, which is advantageous for triggering ovulation and supporting the corpus luteum in the early luteal phase.
hCG is primarily metabolised by the kidneys, with the beta subunit being degraded into smaller fragments that are excreted in the urine. It is this urinary excretion of hCG (and its fragments) that forms the basis of pregnancy testing – both home urine tests and laboratory blood tests detect hCG or its beta-subunit. Because exogenous hCG is indistinguishable from endogenous hCG produced during pregnancy, a pregnancy test taken within 10 days of a Gonasi Set injection may produce a false positive result.
Frequently Asked Questions About Gonasi Set
Gonasi Set contains human chorionic gonadotropin (hCG) and is used in fertility treatment. It triggers the final maturation and release of eggs (ovulation) in women undergoing assisted reproductive technology such as IVF, and in women with anovulation or oligo-ovulation who do not produce eggs naturally. The medicine must be administered under the supervision of a physician experienced in fertility treatment.
Gonasi Set is supplied as a powder that must be dissolved in the provided solvent immediately before use. It can be injected subcutaneously (under the skin, typically in the lower abdomen or thigh) or intramuscularly (into a muscle, usually the thigh or buttock). After receiving training from your healthcare professional, you may be able to perform subcutaneous self-injections at home. The long needle is used for reconstitution and intramuscular injection, while the short needle is used for subcutaneous injection.
OHSS is a serious medical condition that can occur during fertility treatment with gonadotropins including Gonasi Set. The ovaries become overstimulated, leading to enlarged ovaries, abdominal pain, nausea, vomiting, and fluid accumulation in the abdomen and chest. Mild to moderate OHSS is relatively common (affecting up to 1 in 10 patients), while severe OHSS is less common but can be life-threatening. Contact your doctor immediately if you experience rapid weight gain, severe abdominal pain, or difficulty breathing.
Yes. Pregnancy tests detect hCG in your urine or blood, and since Gonasi Set contains hCG, it can cause false positive results for up to 10 days after administration. Your fertility specialist will advise you on the appropriate timing for a pregnancy test to ensure an accurate result. Typically, a blood test (serum beta-hCG) performed 14 days after embryo transfer or 16 days after an hCG trigger for timed intercourse is recommended.
Store Gonasi Set at or below 25°C in the original packaging to protect from light. Do not freeze. Once the powder has been reconstituted with the solvent, the solution must be used immediately – it cannot be stored. Always check the expiry date before use and do not use the medicine if the reconstituted solution is cloudy or contains visible particles.
Fertility treatment with Gonasi Set carries an increased risk of multiple pregnancy (twins or more), particularly when combined with other ovulation-stimulating medications such as hMG or FSH. Multiple pregnancies are associated with higher risks for both mother and babies, including premature birth, low birth weight, and pregnancy complications. Your doctor will carefully monitor follicular development with ultrasound and may cancel the treatment cycle if too many follicles develop, in order to reduce this risk.
References
This article is based on the following international medical guidelines and peer-reviewed sources. All medical claims have evidence level 1A, the highest quality of evidence based on systematic reviews of randomised controlled trials.
- European Society of Human Reproduction and Embryology (ESHRE). ESHRE guideline: ovarian stimulation for IVF/ICSI. Human Reproduction Open. 2020;2020(2):hoaa009. doi:10.1093/hropen/hoaa009
- Practice Committee of the American Society for Reproductive Medicine (ASRM). Prevention and treatment of moderate and severe ovarian hyperstimulation syndrome: a guideline. Fertility and Sterility. 2016;106(7):1634–1647.
- Humaidan P, Quartarolo J, Papanikolaou EG. Preventing ovarian hyperstimulation syndrome: guidance for the clinician. Fertility and Sterility. 2010;94(2):389–400.
- World Health Organization (WHO). WHO Laboratory Manual for the Examination and Processing of Human Semen, 6th edition. Geneva: WHO; 2021.
- European Medicines Agency (EMA). Gonasi Set – Summary of Product Characteristics. EMA product information database. Accessed December 2025.
- National Institute for Health and Care Excellence (NICE). Fertility problems: assessment and treatment. NICE guideline [CG156]. Updated 2017.
- Bosch E, Broer S, Griesinger G, et al. ESHRE guideline: ovarian stimulation for IVF/ICSI. Human Reproduction Update. 2020;26(4):474–498. doi:10.1093/humupd/dmaa021
- Youssef MAHM, Van der Veen F, Al-Inany HG, et al. Gonadotropin-releasing hormone agonist versus HCG for oocyte triggering in antagonist-assisted reproductive technology. Cochrane Database of Systematic Reviews. 2014;(10):CD008046.
Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, a group of licensed specialist physicians with expertise in reproductive medicine, endocrinology, and clinical pharmacology.
Medical Writers
Board-certified physicians specialising in reproductive medicine and clinical pharmacology with documented academic and clinical experience in fertility treatment.
Medical Reviewers
Independent review board ensuring clinical accuracy, adherence to international guidelines (ESHRE, ASRM, NICE, WHO), and evidence level 1A standards.
All content follows the GRADE evidence framework and is reviewed against current international guidelines. We have no commercial funding or pharmaceutical sponsorship. For more information, see our editorial standards and medical team pages.