GnRH antagonists in IVF

Pro: Fresh versus frozen embryo transfer. Is frozen embryo transfer the future?

Embryo cryopreservation has been an integral part of ART for close to 40 years and vitrification has boosted overall ART efficacy and safety. Recently, there has been a vivid scientific discussion on whether elective cryopreservation of all embryos (freeze-all) should be pursued for most patients, with a fresh embryo transfer taking place only in selected cases. In terms of efficacy, the available evidence suggests that the freeze-all strategy leads to higher live birth rates after the first embryo transfer compared to the conventional strategy in high responders, while there is no difference in normal responders. There is no evidence to suggest that the freeze-all strategy is inferior to the conventional strategy of fresh transfer when comparing cumulative live birth rates using data from all available randomized controlled trials. The incidence of ovarian hyperstimulation syndrome is significantly reduced in the freeze-all policy. However, regarding obstetric complications and neonatal outcomes, the evidence suggests that each strategy is associated with certain risks and, therefore, there is no approach that could be unequivocally accepted as safer. Similarly, limited evidence does not support the notion that patients would be universally against freeze-all owing to the inevitable delay in pregnancy achievement. Finally, the cost-effectiveness of freeze-all is likely to vary in different settings and there have been studies supporting that this policy can be, under certain conditions, cost-effective. Adoption of the freeze-all policy can also allow for more flexible treatment strategies that have the potential to increase efficacy, reduce cost and make treatment easier for patients and clinics. Importantly, freeze-all does not require the use of any experimental technologies, further training of personnel or the costly acquisition of new equipment. For these reasons, transitioning to the freeze-all policy for most patients appears to be the next logical step in ART.

The Effect of Luteinising Hormone Suppression in In Vitro Fertilisation Antagonist Cycles

Use of GnRH antagonists in IVF stimulation protocols shortens controlled ovarian hyperstimulation (COH) and reduces the risk of ovarian hyperstimulation syndrome (OHSS). However, profound reduction in LH levels has been associated with use of GnRH antagonists. This study aims to determine if LH suppression during GnRH antagonist cycles results in poorer IVF outcomes. This was a prospective pilot longitudinal study where serum LH levels were measured on day 2/3 of the menstrual cycle before COH, 1/2 days following institution of GnRH antagonist and at the day of ovulation trigger. A threshold of LH <0.5 IU/L was used to define profound LH suppression. Data on IVF outcomes was collected. Logistic regression analysis was used to investigate risk factors associated with LH suppression following GnRH antagonist IVF treatment. Ninety-one eligible women were recruited. Women underwent a standard antagonist cycle with Puregon 200u and Ganirelix. No participant had LH <0.5 IU/L prior to GnRH antagonist treatment, and 27 participants (29.7%) had significant LH suppression at either time point. Predictors of profound LH suppression following GnRH antagonist treatment identified (P < 0.20) were age (OR = 0.80, P = 0.013), no previous ovulation induction (OR = 0.26, P = 0.033) and previous GnRH antagonist IVF cycle (OR = 4.32, P = 0.125). Numbers of oocytes, embryos and ongoing pregnancy rates at 12 weeks gestation in patients with and without LH suppression did not differ significantly. We found associations between clinical characteristics and risk of profound LH suppression in women undergoing GnRH antagonist IVF cycles, but no significant differences in IVF and pregnancy outcomes between women with and without significant LH suppression.

Low Serum LH Levels During Ovarian Stimulation With GnRH Antagonist Protocol Decrease the Live Birth Rate After Fresh Embryo Transfers but Have No Impact in Freeze-All Cycles

OBJECTIVE

To explore the association between serum LH levels and the cumulative live birth rate (CLBR) within one complete cycle, and the impact of serum LH levels on the live birth rate (LBR) after the initial embryo transfer (ET) considering different ET strategies (fresh or freeze-all).

DESIGN

A retrospective cohort study.

SETTING

University-affiliated reproductive center.

PATIENTS

1480 normogonadotrophic women who underwent COS with GnRH antagonist protocol for the first IVF/ICSI attempt.

INTERVENTIONS

The sample was stratified into low and higher LH groups according to serum LH peak levels of <4 (Group A) and ≥4 IU/L (Group B) during COS. Patients were also sub-grouped into conventional fresh/frozen ET cycles and freeze-all cycles.

MAIN OUTCOME MEASURES

The LBR after the initial embryo transfer and the CLBR within one complete cycle.

SECONDARY OUTCOME MEASURES

The numbers of day-3 high-quality embryos, the numbers of embryos available, and the other pregnancy outcomes after the initial ET.

RESULTS

In the whole cohort, the CLBRs decreased significantly in the low (63.1% vs. 68.3%, P=.034) LH group compared to the higher LH group. Subgroup analysis revealed that patients with low LH levels had lower LBR after fresh ET (38.0% vs. 51.5%, P=.005) but comparable LBR after the first frozen-thawed ET (FET) in freeze-all cycles (49.8% vs. 51.8%, P=.517) than patients with higher LH peak levels. Likewise, patients with low LH levels had lower CLBR for conventional fresh/frozen ET cycles (54.8% vs. 66.1%, P=.015) but comparable CLBR for the freeze-all cycles (66.8% vs. 69.2%, P=.414) than those with higher LH levels. Following confounder adjustment, multivariable regression analyses showed that low LH level was an independent risk factor for the CLBR in the whole cohort (odds ratio (OR): 0.756, 95% confidence interval (CI): 0.604-0.965, P=.014) and in patients who underwent the conventional ET strategy (OR: 0.596, 95% CI: 0.408-0.917, P=.017). Moreover, the adverse impact of low LH levels on LBRs maintained statistically significant after fresh transfers (OR: 0.532, 95% CI: 0.353-0.800, P=.002) but not after the first FETs in freeze-all cycles (OR: 0.918, 95% CI: 0.711-1.183, P=.508).

CONCLUSIONS

In comparison with higher LH levels, low LH levels decrease the CLBRs per oocyte retrieval cycle for normogonadotrophic women who underwent COS using GnRH antagonists. This discrepancy may arise due to the significant detrimental effect of low LH levels on the LBRs after fresh embryo transfers.

Comparison of Two Regimens of Gonadotropin-releasing Hormone Antagonists in Clomiphene-gonadotropin Induced Controlled Ovulation and Intrauterine Insemination Cycles: Randomized Controlled Study

Context:

Gonadotropin-releasing hormone (GnRH) antagonists in fixed or flexible regimens are used for prevention of premature luteinizing hormone (LH) surge, however, data comparing these regimens in stimulated intrauterine insemination (IUI) cycles are lacking.

Aims:

The aim of this study is to evaluate the effectiveness of GnRH antagonists in fixed and flexible regimens on the rate of premature luteinization (PL) and ovulation rate in sequential clomiphene-gonadotropin controlled ovulation–IUI cycles.

Settings and Design:

This study was conducted at tertiary care center; this was randomized controlled study.

Materials and Methods:

A total of 45 infertile women randomized into three groups of 15 each received clomiphene citrate + human menopausal gonadotrophin. GnRH antagonist was added according to fixed (n = 15) and flexible (n = 15) protocol. No antagonist in control group (n = 15). PL was defined as LH level ≥10 mIU/ml and progesterone level ≥1.0 ng/ml.

Statistical Analysis:

Mean values compared using the Student's t-test or one-way analysis of variance. Categorical variables distribution tested using either Pearson's Chi-square or Fisher's exact test as appropriate.

Results:

Of a total of 45 women, 58% (n = 26) presented with primary and 42% (n = 19) secondary infertility with mean age of 30.8 ± 3.43 years and BMI 26.57 ± 3.22 kg/m². Fixed regimen (3.7%) showed most reduction in PL compared to flexible (15.38%, P = 0.33) or control (36.67%, P = 0.004). On human chorionic gonadotropin day, mean LH (P = 0.002) and progesterone (P = 0.079) levels in fixed, flexible, and control groups were as follows: 5.04 ± 5.47 mIU/ml, 3.95 ± 4.16 mIU/ml, 9.57 ± 7.91 mIU/ml, and 0.409 ± 0.320 ng/ml, 0.579 ± 0.727 ng/ml, and 1.033 ± 1.022 ng/ml, respectively. Ovulation (P = 0.813) and pregnancy rates (P = 0.99) were 88.9%, 84.6%, and 90% and 22.2%, 19.23%, and 10% in fixed, flexible, and control groups, respectively.

Conclusions:

Addition of antagonist in any regimen appears to lower PL rates and improve pregnancy rates in controlled ovarian stimulation and IUI cycles.

The state of "freeze-for-all" in human ARTs

The recent development of vitrification technologies and the good outcomes obtained in assisted reproduction technologies have supported new indications for freezing and segmentation of treatment. Beyond OHSS prevention and avoidance of embryo transfers in the setting of an adverse endocrinological profile or endometrial cavity, we have witnessed a trend to shift fresh embryo transfers to frozen embryo transfers in many programs. We critically review the available evidence and suggest that freeze-all is not "for all," but should be individualized.

A fresh look at the freeze-all protocol: a SWOT analysis

The 'freeze-all' strategy with the segmentation of IVF treatment, namely with the use of a GnRH antagonist protocol, GnRH agonist triggering, the elective cryopreservation of all embryos by vitrification and a frozen-thawed embryo transfer in a subsequent cycle, has become more popular. However, the approach still encounters drawbacks. In this opinion paper, a SWOT (strengths, weaknesses, opportunities and threats) analysis sheds light on the different aspects of this strategy.

What should be the protocol selection after failure of in-vitro fertilization at normoresponder patients: Agonist or antagonist?

Objective:

Evaluation of the impact of agonist or antagonist protocol selection on pregnancy outcomes after failure of in-vitro fertilization (IVF) treatment cycles which were down regulated with Gonadotropin Releasing Hormone (GnRH) agonist.

Materials and Methods:

This was a retrospective study. Two hundred and sixty nine patients who were treated with GnRH agonist protocol between years 2002-2012 at an IVF unit and underwent a second attempt following one year period after failure of IVF enrolled in the study. Age, basal FSH levels, antral follicle counts, duration of induction, the number of yielded oocytes, the number of transferred embryos and the transfer days, clinical and ongoing pregnancy rates were evaluated for each treatment cycle.

Results:

Normoresponder patients were separated into two groups according to the agonist or antagonist protocol selection at the second attempt and the results of two consequent IVF cycles were compared. There were no statistically significant difference between the groups for the dosage of administered gonadotropin, duration of induction, the count of yielded oocytes, the day and the number of transferred embryos (p>0.05). Furthermore the fertilization rate, clinical and ongoing pregnancy rates were similar in two groups.

Conclusion:

The selection of antagonist treatment is effective as agonist protocols at normoresponder patients after failure of IVF.

Fertility drugs, reproductive strategies and ovarian cancer risk

Several adverse effects have been related to infertility treatments, such as cancer development. In particular, the relationship between infertility, reproductive strategies, and risk of gynecological cancers has aroused much interest in recent years. The evaluation of cancer risk among women treated for infertility is very complex, mainly because of many factors that can contribute to occurrence of cancer in these patients (including parity status). This article addresses the possible association between the use of fertility treatments and the risk of ovarian cancer, through a scrupulous search of the literature published thus far in this field. Our principal objective was to give more conclusive answers on the question whether the use of fertility drug significantly increases ovarian cancer risk. Our analysis focused on the different types of drugs and different treatment schedules used. This study provides additional insights regarding the long-term relationships between fertility drugs and risk of ovarian cancer.

Breast cancer risk after exposure to fertility drugs

In recent years, there has been an increase in the diagnosis of infertility. In industrialized countries, approximately 15% of couples experience this problem today, with a negative impact on quality of life. For this reason, assisted reproductive technologies and other treatments, finalized to overcome infertility, have become very common in clinical practice. For a long time, different ovulation-inducing drugs have been used for ovarian follicle stimulation, either as independent therapies or treatments used during in vitro fertilization cycles. Despite this long-term use, the medical care for infertility gave rise to a lively debate about the potential risk of developing breast cancer that has never been settled. Many studies have been conducted to address this question; but their results have been, and still are, contradictory. The aim of this review is to determine the potential link between the use of fertility drugs and the risk of developing breast cancer in women treated for infertility.

Effectiveness of GnRH antagonist in the treatment of patients with polycystic ovary syndrome undergoing IVF: a systematic review and meta analysis

OBJECTIVE

To systematically evaluate the effectiveness of the gonadotropin-releasing hormone (GnRH) antagonist on in vitro fertilisation (IVF) in patients with polycystic ovary syndrome (PCOS).

METHODS

Nine types of databases were searched by computer, and nine types of relevant journals were searched manually. Randomized, controlled trials of the effects of the GnRH antagonist and GnRH agonist on IVF-ET treatment in the patients with PCOS were included. A meta-analysis was conducted following a quality evaluation.

RESULTS

Seven published studies (755 patients) were included. A meta-analysis was conducted following a quality evaluation. There were no significant differences in the amount of gonadotropin (Gn) (MD = -2.05; 95% CI: -4.14-0.05], E2 levels on the day of hCG administration (MD = -156.13; 95% CI: -389.91-77.64), the number of oocytes retrieved (MD = -0.38; 95% CI: -2.32-1.56), the clinical pregnancy rate (Peto OR = 1.08; 95% CI: 0.80-1.45), and the abortion rate (Peto OR = 0.91; 95% CI: 0.54-1.53) between the GnRH antagonist group and the GnRH agonist group. The OHSS rate of the GnRH antagonist group was lower than that of the GnRH agonist group, and the difference was statistically significant (Peto OR = 0.36; 95% CI: 0.25-0.52).

CONCLUSIONS

Compared with the GnRH agonist protocol, the GnRH antagonist protocol could significantly reduce the risk of OHSS. The clinical pregnancy rates for these two protocols were similar.

Endometrial gene expression in the early luteal phase is impacted by mode of triggering final oocyte maturation in recFSH stimulated and GnRH antagonist co-treated IVF cycles

STUDY QUESTION

Do differences in endometrial gene expression exist after ovarian stimulation with four different regimens of triggering final oocyte maturation and luteal phase support in the same patient?

SUMMARY ANSWER

Significant differences in the expression of genes involved in receptivity and early implantation were seen between the four protocols.

WHAT IS KNOWN ALREADY

GnRH agonist triggering is an alternative to hCG triggering in GnRH antagonist co-treated cycles, resulting in an elimination of early ovarian hyperstimulation syndrome. Whereas previous studies have revealed a low ongoing clinical pregnancy rate after GnRH agonist trigger due to a high early pregnancy loss rate, despite supplementation with the standard luteal phase support, more recent studies, employing a 'modified' luteal phase support including a bolus of 1500 IU hCG on the day of oocyte aspiration, have reported ongoing pregnancy rates similar to those seen after hCG triggering.

STUDY DESIGN, SIZE DURATION

A prospective randomized study was performed in four oocyte donors recruited from an oocyte donation program during the period 2010-2011.

PARTICIPANTS, MATERIALS, SETTING, METHODS

Four oocyte donors in a university IVF center each prospectively underwent four consecutive stimulation protocols, with different modes of triggering final oocyte maturation and a different luteal phase support, followed by endometrial biopsy on Day 5 after oocyte retrieval. The following protocols were used: (A) 10 000 IU hCG and standard luteal phase support, (B) GnRH agonist (triptorelin 0.2 mg), followed by 1500 IU hCG 35 h after triggering final oocyte maturation, and standard luteal phase support, (C) GnRH agonist (triptorelin 0.2 mg) and standard luteal phase support and (D) GnRH agonist (triptorelin 0.2 mg) without luteal phase support. Microarray data analysis was performed with GeneSpring GX 11.5 (RMA algorithm). Pathway and network analysis was performed with the gene ontology software Ingenuity Pathways Analysis (Ingenuity® Systems, www.ingenuity.com, Redwood City, CA, USA). Samples were grouped and background intensity values were removed (cutoff at the lowest 20th percentile). A one-way ANOVA test (P< 0.05) was performed with Benjamini-Hochberg multiple testing correction.

MAIN RESULTS

Significant differences were seen in endometrial gene expression, related to the type of ovulation trigger and luteal phase support. However, the endometrial gene expression after the GnRH agonist trigger and a modified luteal phase support (B) was similar to the pattern seen after the hCG trigger (A).

LIMITATIONS, REASONS FOR CAUTION

The study was performed in four oocyte donors only; however, it is a strength of the study that the same donor underwent four consecutive stimulation protocols within 1 year to avoid inter-individual variations.

WIDER IMPLICATIONS OF THE FINDINGS

These endometrial gene-expression findings support the clinical reports of a non-significant difference in live birth rates between the GnRH agonist trigger and the hCG trigger, when the GnRH agonist trigger is followed by a bolus of 1500 IU hCG at 35 h post trigger in addition to the standard luteal phase support.

STUDY FUNDING/ COMPETING INTERESTS

This study was supported by an un-restricted research grant by MSD Belgium.

TRIAL REGISTRATION NUMBER

EudraCT number 2009-009429-26, protocol number 997 (P06034).

Fixed versus flexible gonadotropin-releasing hormone antagonist administration in in vitro fertilization: a randomized controlled trial

OBJECTIVE

To evaluate whether the incidence of luteinizing hormone (LH) rise is reduced by using a flexible compared with a fixed day-6 protocol of GnRH antagonist administration.

DESIGN

Randomized controlled trial.

SETTING

Tertiary university hospital.

PATIENT(S)

Patients undergoing in vitro fertilization (n = 146).

INTERVENTION(S)

Ovarian stimulation was performed using recombinant FSH and GnRH antagonists. GnRH antagonist cetrorelix (0.25 mg/d) was started either on day 6 of stimulation (fixed group) or when LH was >10 IU/L, and/or a follicle with mean diameter >12 mm was present, and/or serum E(2) was >150 pg/mL. Patient monitoring was initiated on day 3 of stimulation.

MAIN OUTCOME MEASURE(S)

Incidence of LH rise.

RESULT(S)

No statistically significant difference was observed between the flexible and fixed groups regarding the incidence of LH rise, which was lower in the flexible group (11.0% vs. 15.1%, difference -4.1%, 95% confidence interval -15.4% to +7.1%). No LH surges were observed in any of the patients studied.

CONCLUSION(S)

Flexible antagonist administration from day 3 onward does not appear to reduce the incidence of LH rises compared with fixed antagonist administration on day 6 of stimulation.

Mild ovarian stimulation for IVF

BACKGROUND

Mild ovarian stimulation for in vitro fertilization (IVF) aims to achieve cost-effective, patient-friendly regimens which optimize the balance between outcomes and risks of treatment.

METHODS

Pubmed and Medline were searched up to end of January 2008 for papers on ovarian stimulation protocols for IVF. Additionally, references to related studies were selected wherever possible.

RESULTS

Studies show that mild interference with the decrease in follicle-stimulating hormone levels in the mid-follicular phase was sufficient to override the selection of a single dominant follicle. Gonadotrophin-releasing hormone antagonists compared with agonists reduce length and dosage of gonadotrophin treatment without a significant reduction in the probability of live birth (OR 0.86, 95% CI 0.72-1.02). Mild ovarian stimulation may be achieved with limited gonadotrophins or with alternatives such as anti-estrogens or aromatase inhibitors. Another option is luteinizing hormone or human chorionic gonadotrophin administration during the late follicular phase. Studies regarding these approaches are discussed individually; small sample size of single studies along with heterogeneity in patient inclusion criteria as well as outcomes analysed does not allow a meta-analysis to be performed. Additionally, the implications of mild ovarian stimulation for embryo quality, endometrial receptivity, cost and the psychological impact of IVF treatment are discussed.

CONCLUSIONS

Evidence in favour of mild ovarian stimulation for IVF is accumulating in recent literature. However, further, sufficiently powered prospective studies applying novel mild treatment regimens are required and structured reporting of the incidence and severity of complications, the number of treatment days, medication used, cost, patient discomfort and number of patient drop-outs in studies on IVF is encouraged.

Different ovarian stimulation protocols for women with diminished ovarian reserve

PURPOSE

To review the available treatments for women with significantly diminished ovarian reserve and assess the efficacy of different ovarian stimulation protocols.

METHODS

Literature research performed among studies that have been published in the Pubmed, in the Scopus Search Machine and in Cohrane database of systematic reviews.

RESULTS

A lack of clear, uniform definition of the poor responders and a lack of large-scale randomized studies make data interpretation very difficult for precise conclusions. Optimistic data have been presented by the use of high doses of gonadotropins, flare up Gn RH-a protocol (standard or microdose), stop protocols, luteal onset of Gn RH-a and the short protocol. Natural cycle or a modified natural cycle seems to be an appropriate strategy. Low dose hCG in the first days of ovarian stimulation has promising results. Molecular biology tools (mutations, single nucleotide polymorphisms (SNPs)) have been also considered to assist the management of this group of patients.

CONCLUSIONS

The ideal stimulation for these patients with diminished ovarian reserve remains a great challenge for the clinician, within the limits of our pharmaceutical quiver.

Initiation of GnRH antagonist on Day 1 of stimulation as compared to the long agonist protocol in PCOS patients. A randomized controlled trial: effect on hormonal levels and follicular development

BACKGROUND The optimal time for GnRH antagonist initiation is still debatable. The purpose of the current randomized controlled trial is to provide endocrine and follicular data during ovarian stimulation for IVF in patients with polycystic ovarian syndrome (PCOS) treated either with a long GnRH agonist scheme or a fixed day-1 GnRH antagonist protocol. METHODS Randomized patients in both groups (antagonist: n = 26; long agonist: n = 52) received oral contraceptive pill treatment for three weeks and a starting dose of 150 IU of follitropin beta. The primary outcome was E(2) level on Day 5 of stimulation, while secondary outcomes were follicular development, LH during ovarian stimulation and progesterone levels. RESULTS Significantly more follicles on days 5, 7 and 8 of stimulation, significantly higher estradiol (E(2)) levels on days 1, 3, 5, 7 and 8 and significantly higher progesterone levels on days 1, 5 and 8 of stimulation were observed in the antagonist when compared with the agonist group. E(2) was approximately twice as high in the antagonist when compared with the agonist group on day 5 of stimulation (432 versus 204 pg ml(-1), P lt; 0.001). These differences were accompanied by significantly lower LH levels on days 3 and 5 and significantly higher LH levels on days 1, 7 and 8 of stimulation in the antagonist when compared with the agonist group. CONCLUSIONS In PCOS patients undergoing IVF, initiation of GnRH antagonist concomitantly with recombinant FSH is associated with an earlier follicular growth and a different hormonal environment during the follicular phase when compared with the long agonist protocol.

Role of gonadotropin-releasing hormone antagonists in poor responders

OBJECTIVE

To evaluate the role of GnRH antagonists in poor-responder protocols.

DESIGN

Literature review.

CONCLUSION(S)

The optimum stimulation protocol for poor responders is unknown. Although many IVF programs currently use GnRH antagonists for poor responders, there have been only four prospective, randomized trials comparing GnRH antagonists to alternate protocols. None of these studies had sufficient power to evaluate a difference in pregnancy rates (PRs), and in all four cases, IVF outcomes were comparable. Nevertheless, interest in the use of GnRH antagonists in poor responders has continued. GnRH antagonists may be associated with simpler stimulation protocols, lower gonadotropin requirements, reduced patient costs, and shorter downtimes between consecutive cycles. However, the greatest advantage of GnRH antagonists may lie in the ability to assess ovarian reserves immediately prior to deciding whether or not to initiate gonadotropin stimulation. The ability to respond to cycle-to-cycle variation in antral follicle counts may allow the optimization of oocyte yield and reduce cycle cancellation rates. It remains to be seen if this approach (initiating gonadotropins only in cycles where an adequate antral follicle count is present) also translates into higher clinical PRs for poor responders.

High-dose recombinant LH add-back strategy using high-dose GnRH antagonist is an innovative protocol compared with standard GnRH antagonist

High daily doses of gonadotrophin-releasing hormone (GnRH) antagonists during the follicular phase of ovarian stimulation were associated with low implantation rates. To test if this occurred because of profound pituitary suppression, the pituitary response was suppressed with a high-dose GnRH antagonist and recombinant LH (rLH) was added back to correct the implantation rate. An open-label, randomized, controlled, prospective clinical study in 60 patients undergoing IVF was performed. GnRH antagonist was initiated on day 6 of stimulation (2 mg/day) together with 375 IU rLH, and maintained until the day of HCG administration. Controls received 0.25 mg/day GnRH antagonist. Fluctuating LH concentrations were present on days 3 and 6 in both groups. This strong fluctuation continued on day 8 and on the day of HCG administration in the control (low-dose) group, where 30% of patients had LH concentrations <1 IU/l on the HCG day. The study (high-dose) group showed stable LH concentrations on day 8 and on the HCG day, with no LH surges. No clinical differences were found between groups. The LH add-back strategy (375 IU/day) rescued the adverse effects that high doses of GnRH imposed on implantation. These results suggest that rLH should be considered during ovarian stimulation with GnRH antagonist.

Actions of gonadotropin-releasing hormone analogues in pituitary gonadotrophs and their modulation by ovarian steroids

Recently, GnRH antagonists (GnRHant) like cetrorelix and ganirelix have been introduced in protocols of controlled ovarian hyperstimulation for assisted reproductive techniques to prevent premature luteinizing hormone (LH) surges. Here we tested, whether the actions of cetrorelix and the GnRH agonist (GnRHag) triptorelin in gonadotrophs are dependent on the steroid milieu. Furthermore, we characterized the actions of cetrorelix and triptorelin on LH secretion and the total LH pool. Female rat pituitary cells were treated either with 0.1 nM triptorelin for 1, 2, 4 and 6 days or for 1, 3, 5 and 6 h or with 1, 10 or 100 nM cetrorelix for 1, 2, 3 and 5 h or for 10 min. Cells were stimulated for 3h with different concentrations of GnRH (10 pM-1 microM). For analysis of the total LH pool, which is composed of stored and released LH, cells were lysed with 0.1% Triton X-100 at -80 degrees C overnight. To test, whether the steroid milieu affects the actions of cetrorelix and triptorelin, cells were incubated for 52 h with 1 nM estradiol (E) alone or with combinations of 100 nM progesterone (P) for 4 or 52 h, respectively. Cells were then treated with 0.1 nM triptorelin for 9 h or 1 nM cetrorelix for 3 h and stimulated for 3 h with different concentrations of GnRH (10 pM-1 microM). The suppressive effect of triptorelin on LH secretion was fully accomplished after 3 h of treatment, for cetrorelix only 10 min were sufficient. The concentration of cetrorelix must be at least equimolar to GnRH to block LH secretion. Cetrorelix shifted the EC50s of the GnRH dose-response curve to the right. Triptorelin suppressed total LH significantly (from 137 to 36 ng/ml) after 1 h in a time-dependent manner. In contrast, only high concentrations of cetrorelix increased total LH. In steroid treated cells the suppressive effects of triptorelin were more distinct. One nanomolar cetrorelix suppressed GnRH-stimulated LH secretion of cells not treated with steroids from 10.1 to 3.5 ng/ml. In cells, additionally treated with estradiol alone or estradiol and short-term progesterone, LH levels were higher (from 3.5 to 5.4 or 4.5 ng/ml, respectively). In cells co-treated with estradiol and progesterone for 52 h LH secretion was only suppressed from 10.1 to 9.5 ng/ml. Steroid treatments diminished the suppressive effect of cetrorelix on LH secretion. In conclusion, the depletion of the total LH pool contributes to the desensitizing effect of triptorelin. The actions of cetrorelix and triptorelin are dependent on the steroid milieu.

Progesterone supplementation to prevent recurrent miscarriage and to reduce implantation failure in assisted reproduction cycles

Implantation failure has been questioned for many cases of recurrent miscarriage and unsuccessful assisted reproduction. The exact cause of implantation failure is not known, but luteal phase defect is encountered in many of these cases. Consequently, women with recurrent miscarriages have been treated with progesterone supplementation with various degrees of success, and a recent meta-analysis has shown trends for improved live birth rates in those women. Progesterone probably acts as an immunological suppressant blocking T-helper (Th)1 activity and inducing release of Th2 cytokines. Numerous studies have confirmed that ovarian stimulation used in assisted reproduction is associated with luteal phase insufficiency, even when gonadotrophin-releasing hormone antagonists are used. In those patients, advanced endometrial histological maturity and a decrease in the concentration of cytoplasmic progesterone receptors are observed. Progesterone supplementation results in a trend towards improved ongoing and clinical pregnancy rates, except in patients treated with human menopausal gonadotrophin-only regimens, in whom ongoing pregnancy rates increase significantly. More randomized controlled trials are needed to increase the power of the currently available meta-analyses to further evaluate progesterone supplementation in both conditions.

Impact of coasting in patients undergoing controlled ovarian stimulation with the gonadotropin-releasing hormone antagonist cetrorelix

Coasting is the most popular modality for the prevention of ovarian hyperstimulation syndrome, but this procedure has not been evaluated in patients undergoing controlled ovarian hyperstimulation (COH) with GnRH antagonists. The impact of coasting in a cycle in which GnRH antagonist is used was evaluated in 29 women, and it was found that coasting did not deleteriously affect the outcome in high-responder patients undergoing COH with GnRH antagonists.

Precycle administration of GnRH antagonist and microdose HCG decreases clinical pregnancy rates without affecting embryo quality and blastulation

The outcome of a novel protocol utilizing precycle gonadotrophin-releasing hormone (GnRH) antagonist administration and LH activity support with microdose recombinant human chorionic gonadotrophin (HCG) was compared to GnRH agonist long protocol used in patients undergoing their first ICSI (n=707) or IVF (n=571) cycles, which had resulted in one or two blastocyst transfers. In GnRH antagonist cycles, cetrorelix acetate (3 mg) was administered s.c. 4 days before FSH stimulation and a repeat dose was given when the lead follicular diameter was 13-14 mm. LH support was provided by recombinant HCG (2.5 microg). Embryo progression and blastulation were evaluated using embryo progression indices and blastocyst quality scores. The tested protocol demonstrated reduced implantation and clinical pregnancy rates as compared with GnRH agonist long protocol, although the embryo progression and blastulation parameters and blastocyst quality were comparable among the groups. Logistic regression models further supported the significant negative impact of GnRH antagonist/microdose HCG protocol on clinical pregnancy rates in both ICSI and IVF patients. Assisted reproduction cycles with fresh blastocyst transfers utilizing precycle GnRH antagonist administration and microdose HCG support resulted in lower implantation and clinical pregnancy rates as compared with GnRH agonist cycles, although the embryo progression and blastulation parameters were comparable.

GnRH agonist to induce oocyte maturation during IVF in patients at high risk of OHSS

The aim of this retrospective study was to evaluate the effectiveness of gonadotrophin-releasing hormone agonist (GnRHa) to trigger oocyte maturation in patients with polycystic ovarian syndrome (PCOS) or previous high response. The outcome of ovarian stimulation and IVF in patients using GnRHa to trigger oocyte maturation after co-treatment with GnRH antagonist (study group) was compared with patients using human chorionic gonadotrophin (HCG) to trigger oocyte maturation after a dual pituitary suppression protocol with oral contraceptive pill (OCP) and GnRHa overlap (control group). All patients received intramuscular progesterone for luteal support but patients in the study group received additional supplementation with oestradiol patches. The mean number of oocytes, proportion of mature oocytes and fertilization rate were similar between the study and control groups. Implantation rate (38.6% versus 45.1%), clinical pregnancy rate (69.6% versus 60.9%) and delivery rate (62.5% versus 56.5%) were similar in the study and control groups respectively. There was one case of moderate ovarian hyperstimulation syndrome (OHSS) in the control group and none in the study group. GnRHa is effective in triggering oocyte maturation in patients with PCOS or previous high response. Further randomized studies are required to evaluate its effectiveness in the prevention of OHSS in this group of patients.

Effect of an oral contraceptive pill on follicular development in IVF/ICSI patients receiving a GnRH antagonist: a randomized study

This randomized controlled study compared the effectiveness of a gonadotrophin releasing hormone (GnRH) antagonist protocol with or without oral contraceptive (OC) pretreatment on the number of oocytes retrieved in IVF or intracytoplasmic sperm injection (ICSI) patients. Sixty-four patients were randomized to start recombinant human FSH (r-hFSH) on day 2 or 3 after OC withdrawal (OC group) or on day 2 of a natural cycle (control group). From stimulation day 6 onwards, all patients were treated with daily (0.5 mg/ml) GnRH antagonist (Antide). OC pretreatment resulted in significantly lower starting concentrations of FSH, LH and oestradiol (P < 0.001) and a thinner endometrium (P < 0.0001). In the early stimulation period, fewer large follicles were found after OC pretreatment, leading to a significantly extended stimulation period (11.6 versus 8.7 days, P < 0.0001) with more follicles on the day of recombinant human chorionic gonadotrophin administration (15.4 versus 12.5, P = 0.02) and more oocytes retrieved (13.5 versus 10.2, P < 0.001) as compared with the control group. GnRH antagonist regimen, pretreated with OC, prevented the early endogenous FSH rise and improved follicular homogeneity, resulting in more oocytes. As a consequence of the extended treatment period, more rhFSH was required.

In a flexible antagonist protocol, earlier, criteria-based initiation of GnRH antagonist is associated with increased pregnancy rates in IVF

BACKGROUND

The purpose of the study was to assess ongoing pregnancy rates across groups of patients treated by IVF, which were defined according to criteria aimed at the prevention of premature LH surge and used for initiating GnRH antagonist.

METHODS

This is a prospective observational cohort study. During the last 3 years, in IVF-ICSI patients undergoing controlled ovarian stimulation (COS) with the antagonist protocol, the antagonist administration was initiated according to at least one of the following patient-specific criteria: (i) at least one follicle measuring >14 mm; (ii) estradiol levels >600 pg/ml; and (iii) LH levels >10 IU/l. Based upon these criteria, 208 cases of normal responders were analysed and categorized into three groups according to the starting day of the regimen: group D4 (n = 40) for day 4, group D5 (n = 98) for day 5 and group D6 (n = 70) for day 6. The main outcome measure was the ongoing pregnancy rate per started cycle.

RESULTS

The total number of patients in the D4 and D5 groups (138 out of 208), who received the antagonist earlier, was considerably larger compared with that of D6 (70 out of 208). Ongoing pregnancy rates were 37.5, 34.7 and 18.6% for groups D4, D5 and D6, respectively. Patients who initiated the GnRH antagonist on days 4 and 5 had statistically significant higher pregnancy rates compared with day 6. Rapid response, causing earlier antagonist administration initiation, according to the proposed criteria for the prevention of premature LH surges, and the absence of premature luteinization, as evidenced by normal progesterone levels on HCG day, were found to be independent positive predictive factors for favourable IVF outcome.

CONCLUSIONS

The employment of an algorithm of criteria, aimed at the prevention of premature LH surges in a flexible antagonist protocol, resulted in antagonist initiation earlier than on stimulation day 6 in a significant proportion of patients. In those patients, a higher pregnancy rate was observed.

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.

Tailoring FSH and LH administration to individual patients

Many clinical trials have been carried out to find the optimal gonadotrophin starting dose for IVF. The consensus for patients undergoing first treatment and <40 years old is a range stretching from 150 to 250 IU/day. The varying ovarian response to gonadotrophins may be due to factors such as age, basal FSH, number of antral follicles and body mass index, all of which should be taken into account before choosing the type of protocol and the amount of gonadotrophins to use. Increasing the dose of recombinant FSH does not compensate for the age-related decline in retrievable oocytes. Higher doses of gonadotrophins are required in overweight patients, but enhanced protocols are thought to only marginally improve live birth rates in obese women. The actual role of LH in controlled ovarian stimulation is still a matter of debate. A therapeutic 'window' of LH concentrations, below which oestradiol production is inadequate and above which LH may be detrimental to follicular development has been described.