Triggering of ovulation in human menopausal gonadotrophin-stimulated cycles: comparison between intravenously administered gonadotrophin-releasing hormone (100 and 500  g), GnRH agonist (buserelin, 500  g) and human chorionic gonadotrophin (10 000 IU)

Abstract

We studied the peri-ovulatory and luteal phases in 38 human menopausal gonadotrophin (HMG)-stimulated cycles, in which ovulation was triggered with four different i.v. bolus ovulation triggers: 100 micrograms gonadotrophin-releasing hormone (GnRH; group A, n = 9), 500 micrograms GnRH agonist (GnRHa; group B, n = 10), 10,000 IU human chorionic gonadotrophin (HCG; group C, n = 10) and 500 micrograms GnRH (group D, n = 9). Endogenous luteinizing hormone (LH) surges occurred in all cycles of groups A, B and D. The rise was slowest but highest in group B (P < 0.0001) and lowest in group A. Although the t0 serum oestradiol values were similar in all groups, day +8 oestradiol and day +4 and +8 progesterone concentrations were higher in group C (P < 0.05). At day +4 and +8, serum LH concentrations were lowest (P < 0.01) but follicle stimulating hormone (FSH) concentrations were higher. Clinically, day +8 luteal scores showed a more conspicuous degree of ovarian hyperstimulation in the HCG group (P = 0.0292). Luteal insufficiency, defined as cycles with progesterone concentrations of < 8 ng/ml, occurred much more frequently in groups A, B and D than in group C (day +4: P < 0.0003; day +8: P < 0.0001), despite progesterone supplementation. Three pregnancies (one in group C and two in group D) and one moderate case of ovarian hyperstimulation syndrome (OHSS) (in a non-conceptional group D cycle) occurred. These findings show that (i) ovulation occurs and pregnancy can be achieved following an endogenous LH surge induced by GnRH and its agonists, (ii) a high frequency of luteal insufficiency occurs in such cycles even with luteal supplementation and (iii) OHSS cannot be totally prevented by this approach, although cycles with an endogenous LH surge in general result in fewer subclinical signs of ovarian hyperstimulation.

Triggering ovulation with gonadotropin-releasing hormone agonists does not compromise embryo implantation rates

“…Our results parallel those described in IVF-ET (4,8,9,12,13) and indicate that corpus luteum performance is seriously affected when ovulation is induced with GnRH agonist.…”

“…Although luteolysis induced by GnRH agonist does not exclude the possibility of OHSS (9,30,31), in our study none of the donors that ovulated with the GnRH agonist suffered from OHSS; on the other hand, four cases of mild OHSS were detected in the group of donors receiving rhCG (Table 1). Therefore, in our opinion, the use of GnRH agonist instead of hCG to induce final oocyte maturation can be a good alternative to avoid OHSS in assisted reproduction treatments (1,4,6,31).…”

Severe ovarian hyperstimulation syndrome

“…Lanzone et al (78) and Imoedemhe et al (79) were the fi rst to report the successful use of GnRH-a for induction of an endogenous LH/FSH surge for fi nal follicular maturation following exogenous gonadotropin stimulation of the ovaries. Since then, there have been numerous reports of the successful use of GnRH-a to successfully induce follicular maturation in IVF cycles (80,81), as well as ovulation in non-IVF cycles (82,83).…”

“…Gerris et al also reported the occurrence of moderate OHSS in one patient following GnRH-a administration (82), but in this case native GnRH was used, resulting in successful ovulation triggering but without the critical ovarian suppression which is thought to be at least equally important in the prevention of OHSS (91). Casper surveyed a total of 163 cycles in which GnRH-a was used to trigger ovulation in the context of preventing OHSS (92).…”

Le syndrome d’hyperstimulation ovarienne : physiopathologie, facteurs de risque, prévention et prise en charge

“…Comme nous l'avons vu, l'hCG possède un effet biologique beaucoup plus intense que la LH sur une durée de plus de six jours [117]. Gerris et al [118] rapportent des taux d'estradiol et de progestérone beaucoup plus élevés après l'injection d'hCG par rapport à un agoniste de la GnRH. Les doses d'hCG évaluées dans la littérature vont de 2000 à 25 000 UI.…”