Triggering final follicular maturation: hCG, GnRH-agonist, or both, when and to whom?

Gonadotropin releasing hormone agonist triggering for in vitro maturation cycles

The objective was to evaluate the outcomes of in vitro maturation (IVM) cycles using gonadotropin releasing hormone agonist (GnRH-ag) triggering. A retrospective cohort of IVM cycles from January 2015 to December 2019 in a single university-affiliated centre was examined. Main outcome measures were: (i) IVM maturation rate; and (ii) IVM maturation result. Secondary outcome measures were: (i) metaphase II (MII) rate on the day of egg retrieval; (ii) final MII maturation rate; and (iii) pregnancy rates. A total of 98 IVM cycles were performed during the study period: 50 (51%) were triggered with GnRH-ag (17 received FSH priming and 33 did not) and 48 cycles (49%) were triggered by hCG (37 with FSH priming and 11 without). A significant (p = 0.01) difference was noticed in maturation rate on egg retrieval day, in favour of the GnRH-ag group, although not in the final maturation rate achieved. Pregnancy rates were comparable between treatment sub-groups. GnRH-ag triggering in IVM cycles is an optional triggering mode and can be considered an acceptable option, especially when fertility preservation is a concern. GnRH agonists resulted in higher maturation rate on day of oocyte retrieval, but no difference in the total maturation rate.

GnRH Agonist versus hCG Trigger in Ovulation Induction with Intrauterine Insemination: A Randomized Controlled Trial

This study is aimed at comparing clinical pregnancy rates (CPRs) in patients who are administered either gonadotropin-releasing hormone agonist (GnRHa) or human chorionic gonadotropin (hCG) for ovulation trigger in intrauterine insemination (IUI) cycles. A prospective randomized comparative study was conducted at Hue University Hospital in Vietnam. A total of 197 infertile women were randomly assigned to receive either GnRHa trigger (n = 98 cycles) or hCG trigger (n = 99 cycles) for ovulation trigger. Patients returned for ultrasound monitoring 24 hours after IUI to confirm ovulation. A clinical pregnancy was defined as the presence of gestational sac with fetal cardiac activity. There was no difference in ovulation rates in either group receiving GnRHa or hCG trigger for ovulation. Biochemical and CPR were higher in patients who received hCG (28.3% and 23.2%) versus GnRHa (14.3% and 13.3%) (p = 0.023, OR 0.42, 95%CI = 0.21 - 0.86 and p = 0.096, OR 0.51, 95%CI = 0.24 - 1.07, respectively). After adjusting for body mass index (BMI) and infertility duration, there was no difference in CPR between the two groups (OR 0.58, 95% CI 0.27-1.25, p = 0.163). In conclusion, the use of the GnRHa to trigger ovulation in patients undergoing ovulation induction may be considered in patients treated with IUI.

Novel Concepts for Inducing Final Oocyte Maturation in In Vitro Fertilization Treatment

Infertility affects one in six of the population and increasingly couples require treatment with assisted reproductive techniques. In vitro fertilization (IVF) treatment is most commonly conducted using exogenous FSH to induce follicular growth and human chorionic gonadotropin (hCG) to induce final oocyte maturation. However, hCG may cause the potentially life-threatening iatrogenic complication "ovarian hyperstimulation syndrome" (OHSS), which can cause considerable morbidity and, rarely, even mortality in otherwise healthy women. The use of GnRH agonists (GnRHas) has been pioneered during the last two decades to provide a safer option to induce final oocyte maturation. More recently, the neuropeptide kisspeptin, a hypothalamic regulator of GnRH release, has been investigated as a novel inductor of oocyte maturation. The hormonal stimulus used to induce oocyte maturation has a major impact on the success (retrieval of oocytes and chance of implantation) and safety (risk of OHSS) of IVF treatment. This review aims to appraise experimental and clinical data of hormonal approaches used to induce final oocyte maturation by hCG, GnRHa, both GnRHa and hCG administered in combination, recombinant LH, or kisspeptin. We also examine evidence for the timing of administration of the inductor of final oocyte maturation in relationship to parameters of follicular growth and the subsequent interval to oocyte retrieval. In summary, we review data on the efficacy and safety of the major hormonal approaches used to induce final oocyte maturation in clinical practice, as well as some novel approaches that may offer fresh alternatives in future.