Summary of GnRH Antagonists Utilized in In vitro fertilization treatments Treatments


GnRH Agonists and Antagonists for NEET/AIIMS/USMLE/FMGE/PLAB

Video taken from the channel: Ranjan Kumar Patel


When should the antagonist be started in an IVF cycle?

Video taken from the channel: Fertility Courses


Scheduling GnRH antagonist cycles by Barış Ata

Video taken from the channel: Dr Barış Ata


GnRH agonist versus antagonist for ovarian stimulation: Pros & Cons by Peter Kovacs Part 1

Video taken from the channel: Dr. Gautam Allahbadia


What Is the Antagonist Protocol in IVF?

Video taken from the channel: fertilityauthority


GnRH Antagonist Protocols

Video taken from the channel: Amit Emcure


Infertility Treatments 2018

Video taken from the channel: Christopher Morosky

GnRH antagonists are injectable medications that are used during IVF treatment. They prevent premature ovulation, so your doctor will be able to retrieve the eggs from the ovaries before they are released and “lost.” Don’t confuse GnRH agonists (like Lupron) with GnRH antagonists. Specifically, they’re used as part of an in vitro fertilization (IVF) cycle.

What do GnRH antagonists do? GnRH antagonists are used in an IVF cycle to prevent ovulation. This allows your fertility doctor to control egg development and retrieve the eggs at the best time to ensure that your treatment is most likely to work. GnRH antagonists are used to trigger ovulation in assisted reproductive treatments such as AI, IVF, or ICSI. Its administration may cause the following effects: GnRH antagonists binds to the receptor, therefore GnRH cannot bind (competitive blockage).

Receptors are placed in the surface of the pituitary gonadotropic cells. GnRH antagonists (e.g. Ganirelix, Cetrotide, and Orgalutron) are currently used with many controlled ovarian stimulation (COS) protocols. The conventional approach is to administer 250mcg antagonist, daily starting from the 6 th -8th day after commencing ovarian stimulation with gonadotropins. GnRH Antagonists GnRH antagonists are synthetic analogs of GnRH that bind to the GnRH receptors in the pituitary, rapidly suppressing the secretion of gonadotropins.

Suppression is sustained throughout the time during which GnRH antagonists are administered and reversible within 1–2 weeks when treatment is. GnRH (Gonadotrophin Releasing Hormone) agonists are drugs that can help to stop premature ovulation and increase the chances of pregnancy during IVF and IUI treatments. If you ovulate early, we often get fewer eggs and the eggs tend to be lower quality and less useful for IVF. GnRH agonists work by essentially ‘shutting down’ the pituitary.

Gonadotropin-releasing hormone antagonists (GnRH antagonists) are a class of medications that antagonize the gonadotropin-releasing hormone receptor (GnRH receptor) and thus the action of gonadotropin-releasing hormone (GnRH). They are used in the treatment of prostate cancer, endometriosis, uterine fibroids, female infertility in assisted reproduction, and for other indications. It can be estimate, on a global scale that around 10%-12% of all IVF cycles are being performed with the use of GnRH antagonists. Interesting to find is that the 37% used daily injection with decreasing the dose by half when they start stimulation. The use of nasal spay is still very popular.

10% still issue the depot GnRH agonist preparations. GnRH agonists and antagonists are both synthetic analogs of the GnRH peptide hormone, and achieve castrate testosterone levels by shutting down the GnRH-mediated release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the anterior. The majority of randomized clinical trials clearly shows that in “in Vitro” Fertilization and Embryo Transfer, the combination of exogenous Gonadotropin plus a Gonadotropin Releasing Hormone (GnRH) agonist, which is able to suppress pituitary FSH and LH secretion, is associated with increased pregnancy rate as compared with the use of gonadotropins without a GnRH agonist.

Protocols with GnRH antagonists.

List of related literature:

The introduction of GnRH antagonists allows for a careful reevaluation of current IVF strategies.

“Yen & Jaffe's Reproductive Endocrinology E-Book” by Jerome F. Strauss, Robert L. Barbieri
from Yen & Jaffe’s Reproductive Endocrinology E-Book
by Jerome F. Strauss, Robert L. Barbieri
Elsevier Health Sciences, 2009

GnRH antagonists in ovarian stimulation for IVF.

“Berek & Novak's Gynecology” by Jonathan S. Berek
from Berek & Novak’s Gynecology
by Jonathan S. Berek
Wolters Kluwer Health, 2019

The use of GnRH antagonists in IVF protocols also reduces the risk of OHSS.

“Textbook of Assisted Reproductive Techniques: Two Volume Set” by David K. Gardner, Ariel Weissman, Colin M. Howles, Zeev Shoham
from Textbook of Assisted Reproductive Techniques: Two Volume Set
by David K. Gardner, Ariel Weissman, et. al.
CRC Press, 2017

Rescue in vitro fertilization using a GnRH antagonist in hyper-responders from gonadotropin intrauterine insemination (IUI) cycles.

“Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice E-Book” by Robert Resnik, Charles J. Lockwood, Thomas Moore, Michael F Greene, Joshua Copel, Robert M Silver
from Creasy and Resnik’s Maternal-Fetal Medicine: Principles and Practice E-Book
by Robert Resnik, Charles J. Lockwood, et. al.
Elsevier Health Sciences, 2018

Pretreatment with GnRH agonists immediately before IVF cycle initiation appears to be beneficial.

“Endocrinology: Adult and Pediatric E-Book” by J. Larry Jameson, Leslie J. De Groot
from Endocrinology: Adult and Pediatric E-Book
by J. Larry Jameson, Leslie J. De Groot
Elsevier Health Sciences, 2015

Essentially, IVF involves stimulation of multiple ovarian follicle development using recombinant or urinary derived gonadotrophins, with concurrent use of agonadotrophin-releasing hormone (GnRH) agonist or antagonist to prevent a premature LH surge and ovulation before oocytes are harvested.

“Essential Obstetrics and Gynaecology E-Book” by Ian M. Symonds, Sabaratnam Arulkumaran
from Essential Obstetrics and Gynaecology E-Book
by Ian M. Symonds, Sabaratnam Arulkumaran
Elsevier Health Sciences UK, 2013

The IVF therapies were slightly different for the three women, but all three received human chorionic gonadotropin and intravaginal progesterone in addition to either a gonadotropin-releasing hormone (GnRH) agonist, clomiphene and/or recombinant DNA follicle-stimulating hormone.

“Side Effects of Drugs Annual: A Worldwide Yearly Survey of New Data in Adverse Drug Reactions” by Sidhartha D. Ray
from Side Effects of Drugs Annual: A Worldwide Yearly Survey of New Data in Adverse Drug Reactions
by Sidhartha D. Ray
Elsevier Science, 2017

Preventing high-order multiple pregnancies during controlled ovarian hyperstimulation and intrauterine insemination: 3 years’ experience using low-dose recombinant follicle-stimulating hormone and gonadotropin-releasing hormone antagonists.

“Avery's Diseases of the Newborn E-Book” by Christine A. Gleason, Sandra E Juul
from Avery’s Diseases of the Newborn E-Book
by Christine A. Gleason, Sandra E Juul
Elsevier Health Sciences, 2017

Comparison of early versus late initiation of GnRH antagonist co-treatment for controlled ovarian stimulation in IVF: A randomized controlled trial.

“Handbook of In Vitro Fertilization” by David K. Gardner, Carlos Simón
from Handbook of In Vitro Fertilization
by David K. Gardner, Carlos Simón
CRC Press, 2017

Comparisons of GnRH antagonist versus GnRH agonist in supposed normal ovarian responders undergoing IVF: a systematic review and meta-analysis.

“Comprehensive Gynecology E-Book” by Rogerio A. Lobo, David M Gershenson, Gretchen M Lentz, Fidel A Valea
from Comprehensive Gynecology E-Book
by Rogerio A. Lobo, David M Gershenson, et. al.
Elsevier Health Sciences, 2016

Oktay Kutluk

Kutluk Oktay, MD, FACOG is one of the world's foremost experts in fertility preservation as well as ovarian stimulation and in vitro fertilization for infertility treatments. He developed and performed the world's first ovarian transplantation procedures as well as pioneered new ovarian stimulation protocols for embryo and oocyte freezing for breast and endometrial cancer patients.

Mail: [email protected]
Telephone: +1 (877) 492-3666

Bibliography: oktay_bibliography

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