Use of Cetrotide in IVF: Application and Mechanism of Action

By (embryologist), (gynecologist), (embryologist) and (invitra staff).
Last Update: 01/31/2020

Cetrotide is a drug used in the process of controlled ovarian stimulation during fertility treatments.

Its function is to inhibit the production of endogenous gonadotropins in order to keep the ovaries at rest and to be able to control the menstrual cycle in an exogenous way.

The active principle of Cetrotide is cetrorelix, an antagonist of the gonadotropin-releasing hormone (GnRH) which is secreted by the hypothalamus

What is Cetrotide?

Cetrotide is an injectable drug composed of a powder and a solvent.

Its active ingredient is cetrorelix acetate. As a powder excipient it contains mannitol and the solvent is sterile water.

Cetrotide is available on the market in the following formats:

Cetrotide 0.25 mg x 1
a single vial with 0.25 mg of cetrorelix. After the corresponding dilution, each milliliter contains 0.25 mg cetrorelix. This format costs around $245 for a supply of one powder.
Cetrotide 0.25 mg x 7
consists of seven vials, where each vial contains 0.25 mg of cetrorelix After the corresponding dilution, each milliliter contains 0.25 mg cetrorelix. It costs around $1,700 on average.
Cetrotide 3 mg
consists of 3 mg each vial contains 3 mg of cetrorelix After the corresponding dilution, each milliliter contains 1 mg cetrorelix.

Depending on the woman's condition, the doctor will indicate the specific dose of Cetrotide to be administered and will therefore recommend one or the other presentation.

What is Cetrotide for?

GnRH is the gonadotropin-releasing hormone, synthesized by the hypothalamus. It acts on the pituitary gland by causing it to release the gonadotropic hormones LH (luteinizing hormone) and FSH (follicle-stimulating hormone), which exercise their function on the ovary. Thus, the regulation of the menstrual cycle is achieved.

Cetrotide is a GnRH antagonist drug. Its mechanism of action consists of "slowing down" the pituitary gland and preventing endogenous gonadotropins from acting on the ovary. In this way, the gynecologist manages to externally control the process of follicular development in order to obtain a high number of mature eggs in the ovarian puncture. It also prevents spontaneous ovulation and these eggs from being lost.

Cetrotide is used towards the end of in vitro fertilization (IVF) cycle, from the fifth or sixth day of controlled ovarian stimulation until the day of the follicular puncture.

In summary, a woman must first be given a drug containing gonadotropins (FSH and LH) to help her ovarian follicles mature. Then, once the follicles have reached a certain size, Cetrotide is applied so that they do not grow excessively and are kept in the ideal size (over 16-18 millimetres), as well as preventing the premature release of the eggs

The treatment costs may vary significantly depending on the tests or techniques included or not, such as the seminogram, medication, fertility testing, medical visits, prolonged culture or embryo vitrification.

This Tool helps you to find out the exact costs of the different fertility clinics (what's included and what's not) and provides you with lots of useful tips for your first appointment.

How do you use Cetrotide?

Cetrotide should only be used if prescribed by a specialist. Besides, the patient must have been informed and instructed on how to administer the injection subcutaneously.

The dosage of Cetrotide will also have been indicated by the doctor, as well as the exact day and time of administration.


Before each injection of Cetrotide it will be necessary to reconstruct the drug, i.e. mix the powder with the solvent.

The woman or person who will be giving the injection will have to wash her hands and follow the instructions below:

  1. Remove the plastic cap from the glass vial where the powder is. Clean the aluminium ring and the rubber stopper with an alcohol-soaked swab.
  2. Take the mixing needle (yellow) and remove the wrapper. Take the syringe pre-filled with solvent and remove the cap. Screw the needle into the syringe and unscrew it.
  3. Penetrate the needle through the center of the rubber stopper on the vial. Once the syringe needle is in the vial, squeeze the plunger slowly to inject the water.
  4. Mix the powder contained in the vial with the solvent in the syringe. Therefore, make small, gentle rotations of the wrist until a clear solution is obtained. Do not shake vigorously to prevent bubbles or foam from forming.
  5. Place the vial upside down and refill the syringe with the solution from the vial by pulling the plunger. It is important to remove the entire contents of the bottle so that the medicine is not lost.
  6. Put the cap back on the needle and unscrew it from the syringe.

It is important to keep in mind that the drug should not be used if the solution contains particles or if it is not clear (clear and well-diluted).


The injection of Cetrotide must be done immediately after preparing the compound, before the active ingredient is no longer dissolved.

To do this, the preparation needle must be replaced with the injection needle (grey), which is slightly thinner than the previous one.

Once the needle is in place, the plunger is gently pushed until all the bubbles have been expelled and a small drop has come out.

The abdominal area where the subcutaneous injection is to be made is then cleaned with alcohol. With one hand, gently pinch the abdominal area and remove a small roll, with the other hand, insert the needle and press the plunger gently.

It is advisable to change the injection site every day to reduce irritation.

Contraindications and side effects

The application of Cetrotide is not recommended in women who have allergy or hypersensitivity to the active ingredient, any of its excipients or GnRH analogues.

It is also not indicated in the following cases:

  • Women who are pregnant or suspected of being pregnant
  • Breastfeeding women
  • Postmenopausal women
  • Women with a high predisposition to allergies

On the other hand, the most common adverse reactions to Cetroride are related to the application of the drug, such as swelling and skin reactions at the injection site.

Another effect observed is mild to moderate ovarian hyperstimulation syndrome (OHSS), although this syndrome is becoming less frequent.

Headaches and nausea have been described as rare disorders, occurring in a range from 1 in 1,000 to 1 in 100 women.

FAQs from users

Can I still undergo IVF when I'm allergic to Cetrotide?

By Paloma de la Fuente Vaquero M.D., Ph.D., M.Sc. (gynecologist).

Yes, there are different protocols in controlled ovarian stimulation. As for the protocol with antagonists (also called short protocol), the use of Cetrotride (cetrorelix acetate) is included, but other antagonist drugs such as Orgalutran (ganirelix) can also be used. As for the long protocol, for pituitary gland arrest, other drugs called agonists are used. Both protocols have demonstrated the same reproductive efficacy, but it is chosen according to the patient's profile.

When should I start taking my Cetrotide shots?

By Paloma de la Fuente Vaquero M.D., Ph.D., M.Sc. (gynecologist).

Cetrotide is a drug included in the so-called antagonist drugs, its main function is to prevent spontaneous ovulation.

There are two protocols for the administration of the antagonist drugs. One consists of a single dose (3 mg subcutaneously) with the possibility of repeating it after 72 hours and the other involves a multiple dose (0.25 mg per day subcutaneously). In our environment, the most widely used protocol is the multiple dose.

The antagonist drug should be started on the sixth day of stimulation or when there is a follicle larger than 14 mm. Both protocols are valid and can be used in assisted reproduction treatments.

Where should I inject Cetrotide?

By Andrea Rodrigo B.Sc., M.Sc. (embryologist).

Cetrotide should be placed in the abdominal area, pinching a small amount of skin. It is recommended to vary the injection site daily to avoid the appearance of small bruises or resentments from the injection.

What is the cost of Cetrotide in the U.S?

By Andrea Rodrigo B.Sc., M.Sc. (embryologist).

A single vial with 0.25 mg Cetrotide costs around $245. 7 vials of Cetrotide cost approximately $1,700.

Is Cetrotide the same as Orgalutran?

By Andrea Rodrigo B.Sc., M.Sc. (embryologist).

Although their active ingredients are not exactly the same, both drugs have the same behaviour. They are both GnRH antagonists and therefore have the same function.

Should I keep Cetrotide in the fridge?

By Andrea Rodrigo B.Sc., M.Sc. (embryologist).

It is not necessary to keep the Cetrotide in the refrigerator, nor should it be frozen. It should simply be stored in a place that does not receive direct light and that keeps it at a temperature below 25°C. Therefore, if the room temperature is high, perhaps it is advisable to keep it in the refrigerator.

What should I do if I have forgotten to take Cetrotide?

By Zaira Salvador B.Sc., M.Sc. (embryologist).

If a patient misses a dose of Cetrotide, she should inject it as soon as she remembers and contact her doctor in case she needs to change the stimulation pattern.

It is not recommended to administer a double dose to compensate for the forgotten dose of Cetrotide.

Suggested for you

If you would like more information on the drugs used in assisted reproduction treatments, do not miss out on the following article: Drugs used for ovarian stimulation.

You might also be interested in how the IVF process works in detail: In vitro fertilization (IVF)

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Authors and contributors

 Andrea Rodrigo
Andrea Rodrigo
B.Sc., M.Sc.
Bachelor's Degree in Biotechnology from the Polytechnic University of Valencia. Master's Degree in Biotechnology of Human Assisted Reproduction from the University of Valencia along with the Valencian Infertility Institute (IVI). Postgraduate course in Medical Genetics. More information about Andrea Rodrigo
 Paloma de la Fuente Vaquero
Paloma de la Fuente Vaquero
M.D., Ph.D., M.Sc.
Bachelor's Degree in Medicine from the Complutense University of Madrid, with a Master's Degree in Human Reproduction and a Doctorate in Medicine and Surgery from the University of Seville. Member of the Spanish Fertility Society (SEF) and the Spanish Society of Gynecology and Obstetrics (SEGO), she performs as a gynecologist specializing in assisted reproduction in the clinic IVI Sevilla. More information about Paloma de la Fuente Vaquero
License: 4117294
 Zaira Salvador
Zaira Salvador
B.Sc., M.Sc.
Bachelor's Degree in Biotechnology from the Technical University of Valencia (UPV). Biotechnology Degree from the National University of Ireland en Galway (NUIG) and embryologist specializing in Assisted Reproduction, with a Master's Degree in Biotechnology of Human Reproduction from the University of Valencia (UV) and the Valencian Infertility Institute (IVI) More information about Zaira Salvador
License: 3185-CV
Adapted into english by:
 Romina Packan
Romina Packan
inviTRA Staff
Editor and translator for the English and German edition of inviTRA. More information about Romina Packan

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