GnRH agonist trigger versus hCG trigger in GnRH antagonist in IVF/ICSI cycles: A review article

Abstract

Routinely, a bolus of 5.000-10.000 IU human chorionic gonadotropin (hCG) is used for the final follicular maturation and ovulation as a standard method. HCG has the same effect of luteinizing hormone (LH) with long half-life. It has the long lutheotrophic effect which increases the risk of ovarian hyper stimulation syndrome (OHSS). Recently, gonadotropin-releasing hormone agonist (GnRH-a) trigger has been used for the induction of final follicular maturation and ovulation with the aim of reducing the OHSS risk. Several studies have shown that the releases of endogenous follicular stimulating hormone (FSH) and LH after administration of GnRH agonist in in vitro fertilization (IVF) cycles are able to precede the final follicular maturation leading to removal of fertile oocyte with normal development of the embryo and ultimately pregnancy. But based on the results of some studies, using GnRH-a trigger leads to defect luteal-phase resulting to reduce the implantation and clinical pregnancy rates and also increase abortion in fresh embryo transfer cycles compared to routine IVF cycle with hCG triggering . Also, in recent years, studies have continued to modify the luteal phase support, so that the fresh embryo transfer is possible too. In this review, we examined the benefits, problems, and also ways to reform GnRH agonist triggering complications.

A matched propensity score study of embryo morphokinetics following gonadotropin-releasing hormone agonist versus human chorionic gonadotropin trigger

“…It may reflect a different timing of oocyte maturation leading to an earlier activation pathway. Although the lower pregnancy rates with GnRHa trigger are usually related to its luteolytic effect and its negative effect on endometrial receptivity [24][25][26], the slightly lower pregnancy rate in the GnRHa trigger group in our study may be related to decreased embryo quality as well.…”

“…Matching creates quasi-experimental samples, reducing potential bias caused by the imbalance between the two study groups. GnRHa triggering is usually given to prevent ovarian hyperstimulation syndrome (OHSS) in hyper-responder patients such as women with polycystic ovarian syndrome (PCOS) [24]. Matching of the cycles for maternal age, number of oocytes retrieved, and peak E2 levels was performed in attempt to isolate the effect of the triggering itself on the morphokinetic parameters of the embryos while reducing possible intrinsic maternal physiologic and metabolic influence on the kinetics of embryo development…”

Clinical Pregnancy and Incidence of Ovarian Hyperstimulation Syndrome in High Ovarian Responders Receiving Different Doses of hCG Supplementation in a GnRH-Agonist Trigger Protocol

“…In the last two decades, GnRH-a has been a trigger factor for the final follicle maturation, which significantly reduced the incidence rate of OHSS clinically [ 8 , 9 ]. However, many studies have reported that GnRH-a trigger protocol is prone to luteal insufficiency [ 10 ], resulting in the decrease of clinical pregnancy rate and the increase of early abortion rate [ 11 , 12 ].…”

Dual trigger with gonadotropin-releasing hormone agonist and recombinant human chorionic gonadotropin improves the outcome of intrauterine insemination

“…GnRH-a can stimulate FSH surge and LH surge. FSH surge has a beneficial effect on oocyte maturation and causes cumulus expansion of the oocyte [16][17][18][19][20]22].…”