GnRH antagonist versus long GnRH agonist protocol in poor responders undergoing IVF: a randomized controlled trial

Ageing and ART: a waste of time and money?

In many societies, more and more young women are delaying childbearing until the fourth decade of life. It is well known that fertility is remarkably reduced with increasing age of women in both natural conceptions and assisted reproductive technology (ART). In this chapter, the effect of ageing on the pregnancy rate in ART, and the options available to improve the reproductive outcomes in women of advanced age will be presented after understanding the mechanism of reproductive ageing and the effects of ageing on the reproductive outcomes in normal women. It is important to identify the predictive factors associated with a better treatment outcome.

Interventions for 'poor responders' to controlled ovarian hyperstimulation (COH) in in-vitro fertilisation (IVF)

BACKGROUND

The success of in-vitro fertilisation (IVF) treatment depends on adequate follicle recruitment by using controlled ovarian stimulation with gonadotrophins. Failure to recruit adequate follicles is called 'poor response'. Various treatment protocols have been proposed that are targeted at this cohort of women, aiming to increase their ovarian response.

OBJECTIVES

To compare the effectiveness of different treatment interventions in women who have poor response to controlled ovarian hyperstimulation (are poor responders) in the context of in vitro fertilisation.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials (MDSG), the Cochrane Central Register of Controlled trials (CENTRAL) (The Cochrane Library 2003, Issue 1), MEDLINE (1966 to August 2006), EMBASE (1980 to August 2006) and The National Research Register (NRR). The citation lists of relevant publications, review articles, abstracts of scientific meetings and included studies were also searched. The authors were contacted to identify or clarify data that were unclear from the trial reports.

SELECTION CRITERIA

Only randomised controlled trials (RCTs) comparing one type of intervention versus another for controlled ovarian stimulation of poor responders to a previous IVF treatment, using a standard long protocol were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently scanned the abstracts, identified relevant papers, assessed inclusion and trial quality and extracted relevant data. Validity was assessed in terms of method of randomisation, completeness of treatment cycle and co-intervention. Where possible, data were pooled for analysis.

MAIN RESULTS

Nine trials involving six different comparison groups have been included in this review. Only one trial reported live birth rates. Four groups compared the long protocol with another intervention. Only one comparison group (bromocryptine versus long protocol) reported a higher clinical pregnancy rate per cycle, in the bromocryptine arm (OR 5.60, 95% CI 1.40 to 22.47). Two comparison groups showed a lower number of oocytes in the long protocol group (versus stop and gonadotrophin releasing hormone (GnRH) antagonist protocols). However, two comparison groups also showed lower cancellation rates in the long protocol treatment group (versus stop and GnRHa flare-up protocols). None reported any evident difference in the adverse effects.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support the routine use of any particular intervention either for pituitary downregulation, ovarian stimulation or adjuvant therapy in the management of poor responders to controlled ovarian stimulation in IVF. More robust data from good quality RCTs with relevant outcomes are needed.

Evaluation of the utility of multiple endocrine and ultrasound measures of ovarian reserve in the prediction of cycle cancellation in a high-risk IVF population

BACKGROUND

Unexpectedly poor response leading to IVF cycle cancellation is a distressing treatment outcome. We have prospectively assessed several markers of ovarian reserve in a high risk IVF population to determine their utility in predicting IVF cycle cancellation.

METHODS

Eighty-four women at high risk of cycle cancellation due to raised FSH, previous poor response and/or age > or =40 years attending for high-dose short protocol IVF treatment had baseline measures of FSH, inhibin B, anti-Müllerian hormone (AMH), antral follicle count (AFC) and ovarian volume. A GnRH agonist was then administered and, 24 h later, estradiol (E(2)) and inhibin B measures were repeated.

RESULTS

Fifty-seven per cent of patients in this study had a poor response to stimulation, and 15% were cancelled. Using multivariate logistic regression, we found that day 3 inhibin B levels were the best predictor of cycle cancellation with an area under the receiver operating curve (ROC AUC) = 0.78 (P = 0.017). When only considering baseline variables, mean ovarian volume was the best predictor of cycle cancellation (ROC AUC = 0.78; P = 0.016). AMH concentrations were the best predictor of a poor response (P = 0.003), and AMH was also predictive of cycle cancellation (P = 0.007) with very little inter-cycle variability. None of the parameters studied were predictive of ongoing pregnancy.

CONCLUSIONS

This group of at-risk patients had a high rate of poor response to simulation and cancellation. Although several measures of ovarian reserve were able to predict cycle cancellation, none were able to predict pregnancy. AMH was predictive of both cycle cancellation and poor response with little inter-cycle variability.

Patients with three or less dominant follicles may not be associated with reduced pregnancy rate of in vitro fertilization treatment

OBJECTIVES

The management of poor ovarian responders remains a great challenge in in vitro fertilization (IVF) treatment. This study compared implantation and pregnancy rates among women who developed <or=3 dominant follicles of >or=16 mm in diameter and those who had >3 dominant follicles after ovarian stimulation.

STUDY DESIGN

Retrospective study.

RESULTS

Out of 911 consecutive patients receiving ovarian stimulation between January 2000 and December 2002, 894 (98.1%) patients underwent oocyte retrieval. Women with <or=3 dominant follicles were significantly older, required a longer duration and a higher dosage of gonadotrophin but produced lesser number of developing follicles, number of oocytes aspirated and number of embryos frozen when compared with those with >3 dominant follicles. Despite a significantly higher percentage of non-elective single embryo transfer in women with <or=3 dominant follicles, implantation rate, pregnancy rate and pregnancy outcomes were comparable for women with <or=3 and >3 dominant follicles.

CONCLUSION

Implantation and pregnancy rates appeared to be comparable for women who developed <or=3 and >3 dominant follicles during IVF treatment.

Among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth dependent on the type of analogue used? A systematic review and meta-analysis

This systematic review and meta-analysis aimed to answer the following clinical question: among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth per randomized patient dependent on the type of analogue used? Eligible studies were randomized controlled trials (RCTs), published as a full manuscript in a peer-reviewed journal, that contained sufficient information to allow ascertainment of whether randomization was true and whether equality was present between the groups compared. A literature search identified 22 RCTs comparing GnRH antagonists and GnRH agonists that involved 3176 subjects. Where live birth was not reported in a study that fulfilled the inclusion criteria, an effort was made to contact the corresponding authors to retrieve the missing information. If this was not possible, the reported outcome measure, clinical pregnancy or ongoing pregnancy was converted to live birth in 12 studies using published data (Arce et al., 2005). No significant difference was present in the probability of live birth between the two GnRH analogues [odds ratio (OR), 0.86; 95% confidence intervals (CI), 0.72 to 1.02]. This result remains stable in subgroup analysis that ordered the studies by type of population studied, gonadotrophin type used for stimulation, type of agonist protocol used, type of agonist used, type of antagonist protocol used, type of antagonist used, presence of allocation concealment, presence of co-intervention and the way the information on live birth was retrieved. In conclusion, the probability of live birth after ovarian stimulation for IVF does not depend on the type of analogue used for pituitary suppression.

Optimal stimulation protocols for in vitro fertilization

OBJECTIVE

To update clinicians on different gonadotropin regimens for ovarian stimulation for IVF including the use of urinary and recombinant gonadotropins, the value of added LH to FSH in the stimulation regimen, the use of GnRH agonists and antagonists, and the role of minimal stimulation protocols.

DESIGN

Literature review and critical analysis of major articles during the last five years on ovarian stimulation for IVF.

CONCLUSION(S)

Urinary and recombinant gonadotropins, for ovarian stimulation for IVF, are probably equally safe and effective. The higher cost for recombinant products limits their worldwide use in IVF. Conflicting data exist regarding the benefit of adding LH to FSH in the stimulation regimens. The use of different GnRH-agonists, of varying potency, may account for different levels of LH suppression. Adding LH should be considered in severe situations of LH suppression such as with the use of potent GnRH-agonists or when GnRH-antagonists are introduced during the course of stimulation. GnRH-antagonists provide advantages to patients in terms of fewer injections, shorter stimulation days, and avoidance of adverse effects of agonists. The incidence of ovarian hyperstimulation syndrome is probably less with antagonists compared to agonists, with the option to use an agonist as a surrogate LH surge. Fixed and early start of the antagonist is probably more effective than an individualized and late start. The earlier reported lower pregnancy rates with antagonists compared to agonists is not fully understood and needs to be continually monitored. Minimal stimulation protocols using a combination of clomiphene citrate and gonadotropins are attractive and should be considered in some patients owing to lower costs and acceptable success rates. The optimal stimulation protocol for IVF should be an individualized regimen based on the patient's ovarian physiology and prior IVF experience, if any.

Gonadotrophin-releasing hormone antagonists for assisted conception

BACKGROUND

Gonadotrophin-releasing hormone antagonists produce immediate suppression of gonadotrophin secretion, hence, they can be given after starting gonadotrophin administration. This has resulted in dramatic reduction in the duration of treatment cycle. Two different regimes have been described. The multiple-dose protocol involves the administration of 0.25 mg cetrorelix (or ganirelix) daily from day six to seven of stimulation, or when the leading follicle is 14 to15 mm, until human chorionic gonadotrophin (HCG) administration and the single-dose protocol involves the single administration of 3 mg cetrorelix on day seven to eight of stimulation. Assuming comparable clinical outcome, these benefits would justify a change from the standard long protocol of GnRH agonists to the new GnRH antagonist regimens.

OBJECTIVES

To evaluate the evidence regarding the efficacy of gonadotrophin-releasing hormone (GnRH) antagonists with the standard long protocol of GnRH agonists for controlled ovarian hyperstimulation in assisted conception.

SEARCH STRATEGY

We searched Cochrane Menstrual Disorders and Subfertility Group's Specialised Register, MEDLINE and EMBASE databases from 1987 to February 2006, and handsearched bibliographies of relevant publications and reviews, and abstracts of scientific meetings. We also contacted manufacturers in the field.

SELECTION CRITERIA

Randomized controlled studies comparing different protocols of GnRH antagonists with GnRH agonists in assisted conception cycles were included in this review.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. If relevant data were missing or unclear, the authors have been consulted

MAIN RESULTS

Twenty seven RCTs comparing the GnRH antagonist to the long protocol of GnRH agonist fulfilled the inclusion criteria. Clinical pregnancy rate was significantly lower in the antagonist group. (OR = 0.84, 95% CI = 0.72 - 0.97). The ongoing pregnancy/ live-birth rate showed the same significant lower pregnancy in the antagonist group (P = 0.03; OR 0.82, 95% CI 0.69 to 0.98).However, there was statistically significant reduction in incidence of severe OHSS with antagonist protocol. The relative risk ratio was (P = 0.01; RR 0.61, 95% CI 0.42 to 0.89). In addition, interventions to prevent OHSS (e.g. coasting, cycle cancellation) were administered more frequently in the agonist group (P = 0.03; OR 0.44, 95% CI 0.21 to 0.93).

AUTHORS' CONCLUSIONS

GnRH antagonist protocol is a short and simple protocol with good clinical outcome with significant reduction in incidence of severe ovarian hyperstimulation syndrome and amount of gonadotrophins but the lower pregnancy rate compared to the GnRH agonist long protocol necessitates counseling subfertile couples before recommending change from GnRH agonist to antagonist..

Gonadotropin-releasing hormone (GnRH) antagonist plus recombinant luteinizing hormone vs. a standard GnRH agonist short protocol in patients at risk for poor ovarian response

Various studies have compared the efficacy of GnRH agonists (GnRH-a) and antagonists (GnRH-ant) for controlled ovarian stimulation (COS) in women undergoing IVF. Nevertheless, few data are available about the use of GnRH-ant in poor responders. Here, a flexible protocol providing a gradual increase in the dose of GnRH-ant in association with recombinant LH (rec-LH) administration is compared with the standard GnRH-a flare-up protocol in 133 women at risk for poor ovarian response. The mean number of metaphase 2 oocytes (primary end point) was significantly higher in the antagonist group (5.73 +/- 3.57 vs. 4.64 +/- 2.23, respectively; P<.05).

Follicular fluid vascular endothelial growth factor concentrations are increased during GnRH antagonist/FSH ovarian stimulation cycles

BACKGROUND

The aim of this study was to investigate the effect of GnRH antagonists (GnRH-ant) on follicular fluid vascular endothelial growth factor (FF VEGF).

METHODS

Sixty women undergoing assisted reproduction were randomised (computer-generated randomisation list) and assigned to two different GnRH analogue regimens: GnRH agonist (GnRH-a) (Group A; n = 30) and GnRH-ant (Group B; n = 30).

RESULTS

Mean (+/-S.D.) FF VEGF concentrations were 1598+/-612 pg/mL and 2906+/-1558 pg/mL for Groups A and B, respectively (p < 0.001). In the women treated with GnRH-ant, we found a statistically significant reduction in serum LH levels (1.72+/-0.74 IU/L in Group A versus 0.93+/-0.43 IU/L in Group B, p < 0.001), in serum oestradiol (E2) levels (1562.1+/-410.7 pg/mL in Group A versus 1214.67+/-779.9 pg/mL in Group B, p < 0.05), in FF E2 levels (1146+/-593 ng/mL in Group A versus 621+/-435 ng/mL in Group B, p < 0.05), and in FF androstenedione levels (136+/-55 ng/mL in Group A versus 78+/-31 ng/mL in Group B, p < 0.001), as well as a reduction in the number of pregnancies, though not statistically significant (23.3% in Group A versus 16.6% in Group B).

CONCLUSION

The increase in FF VEGF levels in women treated with GnRH-ant might be explained by a suppression of LH and E2 levels.

GnRH agonist versus GnRH antagonist in poor ovarian responders: a meta-analysis

The aim of this meta-analysis was to compare the efficacy of gonadotrophin antagonist (GnRH-ant) versus GnRH agonist (GnRHa) as coadjuvant therapy for ovarian stimulation in poor ovarian responders in IVF/intracytoplasmic sperm injection cycles. Search strategies included on-line surveys of databases such as MEDLINE , EMBASE and others. A fixed effects model was used for odds ratio (OR) and effect size (weighted mean difference, WMD). Six trials fulfilled the inclusion criteria (randomized controlled trials). There was no difference between GnRH-ant and GnRHa (long and flare-up protocols) with respect to cycle cancellation rate, number of mature oocytes and clinical pregnancy rate per cycle initiated, per oocyte retrieval and per embryo transfer. When the meta-analysis was applied to the two trials that had used GnRH-ant versus long protocols of GnRHa, a significantly higher number of retrieved oocytes was observed in the GnRH-ant protocols [P=0.018; WMD: 1.12 (0.18, 2.05)]. However, when the meta-analysis was applied to the four trials that had used GnRH-ant versus flare-up protocols, a significantly higher number of retrieved oocytes (P=0.032; WMD: -0.51, 95% CI -0.99, -0.04) was observed in the GnRHa protocols. Nevertheless, additional randomized controlled trials with better planning are needed to confirm these results.

GnRH-antagonists in ovarian stimulation for IVF in patients with poor response to gonadotrophins, polycystic ovary syndrome, and risk of ovarian hyperstimulation: a meta-analysis

This article is a systematic review of the literature on utilization of gonadotrophin-releasing hormone antagonists (GnRH-ant) for ovarian stimulation for IVF in special patient groups. Summarized by meta-analysis are the data from randomized controlled trials (RCT) in which GnRH-agonist (GnRH-a) and GnRH-ant were compared (eight RCT for poor response, four RCT for PCOS). Also reviewed are the data from two RCT and 13 retrospective or observational trials in which patients at risk of ovarian hyperstimulation syndrome (OHSS) were triggered with GnRH-agonist instead of HCG. For poor responders, no differences in clinical outcomes were found, except a significantly higher number of cumulus-oocyte complexes in GnRH-antagonist multiple dose protocol as compared to GnRH-agonist long protocol (P=0.05). For PCOS patients, no differences in outcomes were found, except a significantly shorter duration of stimulation, when GnRH-antagonist multiple dose protocol and GnRH-agonist long protocol are compared (P<0.01). However, sample sizes are still small and power to detect subtle differences is therefore limited. For OHSS risk patients triggered with GnRH-agonist, reports on the efficacy of this measure vary in the literature. GnRH-agonist triggering appears to be associated with a reduction in the incidence of mild and moderate OHSS. For prevention of severe OHSS, as yet, only very limited evidence is available.

Gonadotropin-releasing hormone (GnRH) analogues and the ovary: Do GnRH antagonists destroy primordial follicles?

The study by Danforth et al. shows that gonadotropin-releasing hormone (GnRH) antagonists do not protect ovarian follicles from chemotherapy-induced damage and that GnRH antagonists alone reduce primordial follicle numbers in mice. This article discusses the strengths and limitations of the study by Danforth et al., as well as the potential mechanism of action of GnRH antagonists according to the literature.

Reproductive outcome using a GnRH antagonist (cetrorelix) for luteolysis and follicular synchronization in poor responder IVF/ICSI patients treated with a flexible GnRH antagonist protocol

To investigate the possible beneficial effect of a new stimulation protocol (termed 'CRASH') on the outcome of poor responder patients, a multicentre, prospective longitudinal study including a total of 36 women undergoing 72 IVF/intracytoplasmic sperm injection (ICSI) cycles with patients serving as their own controls, was conducted. A poor responder patient was defined as a patient with four or fewer oocytes extracted from five or fewer follicles and with a total FSH consumption exceeding 2000 IU in a preceding long agonist down-regulation protocol. The CRASH protocol included 3 mg of the gonadotrophin-releasing hormone (GnRH) antagonist cetrorelix given in the late luteal phase on cycle day 23. Stimulation with recombinant human FSH (rhFSH) started on cycle day 2, followed by a flexible GnRH antagonist protocol. The results showed significantly more follicles (5.4 versus 3.5), oocytes (4.3 versus 2.4) and transferable embryos (1.8 versus 0.8) with the CRASH protocol as compared with the preceding long protocol (P < 0.005 in all cases). The implantation rate and pregnancy rate per transfer was 18.4 and 38.5% respectively, approaching the clinical outcome of normal responder patients. The CRASH protocol thus may constitute an attractive alternative to conventional protocols for low responder patients, improving their clinical outcome.