Combined treatment with gonadotrophin releasing hormone agonist and gonadotrophins in poor responders to hyperstimulation for in vitro fertilization (IVF): clinical and endocrine results

Gonadotrophin-releasing hormone agonist protocols for pituitary suppression in assisted reproduction

BACKGROUND

Gonadotrophin-releasing hormone agonists (GnRHa) are commonly used in assisted reproduction technology (ART) cycles to prevent a luteinising hormone surge during controlled ovarian hyperstimulation (COH) prior to planned oocyte retrieval, thus optimising the chances of live birth.

OBJECTIVES

To evaluate the effectiveness of the different GnRHa protocols as adjuncts to COH in women undergoing ART cycles.

SEARCH METHODS

We searched the following databases from inception to April 2015: the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library (2015, Issue 3), MEDLINE, EMBASE, CINAHL, PsycINFO, and registries of ongoing trials. Reference lists of relevant articles were also searched.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing any two protocols of GnRHa used in in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) cycles in subfertile women.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed trial eligibility and risk of bias, and extracted the data. The primary outcome measure was number of live births or ongoing pregnancies per woman/couple randomised. Secondary outcome measures were number of clinical pregnancies, number of oocytes retrieved, dose of gonadotrophins used, adverse effects (pregnancy losses, ovarian hyperstimulation, cycle cancellation, and premature luteinising hormone (LH) surges), and cost and acceptability of the regimens. We combined data to calculate odds ratios (OR) for dichotomous variables and mean differences (MD) for continuous variables, with 95% confidence intervals (CIs). We assessed statistical heterogeneity using the I² statistic. We assessed the overall quality of the evidence for the main comparisons using 'Grading of Recommendations Assessment, Development and Evaluation' (GRADE) methods.

MAIN RESULTS

We included 37 RCTs (3872 women), one ongoing trial, and one trial awaiting classification. These trials made nine different comparisons between protocols. Twenty of the RCTs compared long protocols and short protocols. Only 19/37 RCTs reported live birth or ongoing pregnancy.There was no conclusive evidence of a difference between a long protocol and a short protocol in live birth and ongoing pregnancy rates (OR 1.30, 95% CI 0.94 to 1.81; 12 RCTs, n = 976 women, I² = 15%, low quality evidence). Our findings suggest that in a population in which 14% of women achieve live birth or ongoing pregnancy using a short protocol, between 13% and 23% will achieve live birth or ongoing pregnancy using a long protocol. There was evidence of an increase in clinical pregnancy rates (OR 1.50, 95% CI 1.18 to 1.92; 20 RCTs, n = 1643 women, I² = 27%, moderate quality evidence) associated with the use of a long protocol.There was no evidence of a difference between the groups in terms of live birth and ongoing pregnancy rates when the following GnRHa protocols were compared: long versus ultrashort protocol (OR 1.78, 95% CI 0.72 to 4.36; one RCT, n = 150 women, low quality evidence), long luteal versus long follicular phase protocol (OR 1.89, 95% CI 0.87 to 4.10; one RCT, n = 223 women, low quality evidence), when GnRHa was stopped versus when it was continued (OR 0.75, 95% CI 0.42 to 1.33; three RCTs, n = 290 women, I² = 0%, low quality evidence), when the dose of GnRHa was reduced versus when the same dose was continued (OR 1.02, 95% CI 0.68 to 1.52; four RCTs, n = 407 women, I² = 0%, low quality evidence), when GnRHa was discontinued versus continued after human chorionic gonadotrophin (HCG) administration in the long protocol (OR 0.89, 95% CI 0.49 to 1.64; one RCT, n = 181 women, low quality evidence), and when administration of GnRHa lasted for two versus three weeks before stimulation (OR 1.14, 95% CI 0.49 to 2.68; one RCT, n = 85 women, low quality evidence). Our primary outcomes were not reported for any other comparisons.Regarding adverse events, there were insufficient data to enable us to reach any conclusions except about the cycle cancellation rate. There was no conclusive evidence of a difference in cycle cancellation rate (OR 0.95, 95% CI 0.59 to 1.55; 11 RCTs, n = 1026 women, I² = 42%, low quality evidence) when a long protocol was compared with a short protocol. This suggests that in a population in which 9% of women would have their cycles cancelled using a short protocol, between 5.5% and 14% will have cancelled cycles when using a long protocol.The quality of the evidence ranged from moderate to low. The main limitations in the evidence were failure to report live birth or ongoing pregnancy, poor reporting of methods in the primary studies, and imprecise findings due to lack of data. Only 10 of the 37 included studies were conducted within the last 10 years.

AUTHORS' CONCLUSIONS

When long GnRHa protocols and short GnRHa protocols were compared, we found no conclusive evidence of a difference in live birth and ongoing pregnancy rates, but there was moderate quality evidence of higher clinical pregnancy rates in the long protocol group. None of the other analyses showed any evidence of a difference in birth or pregnancy outcomes between the protocols compared. There was insufficient evidence to make any conclusions regarding adverse effects.

Gonadotrophin-releasing hormone agonist protocols for pituitary suppression in assisted reproduction

BACKGROUND

Gonadotrophin-releasing hormone agonists (GnRHa) are used in assisted reproduction technology (ART) cycles to prevent a luteinizing hormone surge. Various protocols have been described in the literature, such as long protocols (continuous and stop or reduce dose, long luteal, or long follicular protocol); short protocols and ultrashort protocols.

OBJECTIVES

To determine the most effective GnRHa protocol as an adjuvant to gonadotrophins in ART cycles.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE, CINHAHL and PsycINFO. Reference lists of relevant articles were also searched. All the searches were updated to August 2010.

SELECTION CRITERIA

Only randomised controlled trials comparing any two protocols of GnRHa in in vitro fertilization (IVF) or intra-cytoplasmic sperm injection (ICSI) cycles were included.

DATA COLLECTION AND ANALYSIS

The primary outcome measure was live births per women. Secondary outcome measures were pregnancy rate, ongoing pregnancy rate, number of oocytes retrieved and amount of gonadotrophins used. Data were independently extracted in 2 x 2 tables by two authors. Odds ratios (OR) with 95% confidence intervals (CI) were calculated after verifying the presence of homogeneity of treatment effect across all trials. For continuous variables mean differences (MD) were calculated.

MAIN RESULTS

Of 29 included studies, 17 compared long with short protocols; two compared long with ultrashort protocols; four compared a follicular versus luteal start of GnRHa; three compared continuation versus stopping the GnRHa at the start of stimulation; three compared continuation of the same dose versus reduced dose of GnRHa and one compared a short versus short stop protocol.There was no evidence of a difference in the live birth rate but this outcome was only reported by three studies.There was evidence of a significant increase in clinical pregnancy rate (OR 1.50, 95% CI 1.16 to 1.93) in a long protocol when compared to a short protocol. That is there is a 50% increase in chance of achieving pregnancy if a long protocol is used as compared to a short protocol, although this difference could range from 16% to 93% increased chance of pregnancy. This difference did not persist when the meta-analysis was done only on the studies with adequate randomisation (OR 1.38, 95% CI 0.93 to 2.05).There was evidence of an increased number of oocytes (MD 1.61, 95% CI 0.18 to 3.04) obtained when a long protocol was used as compared to a short protocol. That is there is a 60% increase in the number of oocytes retrieved when a long protocol is used as compared to a short protocol, although this difference could range from 18% to 304% more oocytes.There was evidence of an increase (MD 12.90, 95% CI 3.29 to 22.51) in the requirement for gonadotrophins in long as compared to short protocols. That is approximately 12.9 more ampoules of gonadotrophins were consumed when a long protocol was used as compared to a short protocol. This difference could range from 3.29 to 22.51 more gonadotrophin ampoules.There was no evidence of a difference in any of the outcome measures for luteal versus follicular start of GnRHa and stopping versus continuation of GnRHa at the start of stimulation.

AUTHORS' CONCLUSIONS

The pregnancy rate was found to be higher when GnRHa was used in a long protocol as compared to a short or ultrashort protocol. There was no evidence of a difference in live birth rate, but this outcome was only reported by three studies. There was no evidence of a difference in the outcomes amongst various long protocols; nor that stopping or reducing GnRHa at the start of stimulation was associated with a reduced pregnancy rate. For all comparison, except a long versus short protocol, there was a lack of power.

[Premature ovarian failure: which protocols?]

This review shows the results of the various studies concerning the protocols applied to the women presenting a premature ovarian failure. Will be thus analyzed the natural cycles (or semi-natural), the increase in the dose of gonadotrophins, the clomiphene citrate and the anti-aromatases, the protocols with GnRH agonists long, short, stop or microdoses, the protocols with GnRH antagonists and the adjuvant treatments: aspirin, nitric oxyde, recombinant LH recombining, growth hormone and androgens. The interest of several protocols is to collect a sufficient number of oocytes (and thus of embryos to be transferred), making it possible to obtain reasonable rates of pregnancy. However, it arises that the rates of pregnancy observed among these women depend not only on their ovarian reserve and their age, but are also function of the type of infertility, of the cycle number and the uterus.

Management of the poor responder: the role of GnRH agonists and antagonists

PURPOSE

Evaluate the relative benefit of various doses and regimens of GnRH agonists (GnRHa) and antagonists (GnRHant) in the management of the poor responder.

METHODS

Review of English language publications with an emphasis on prospective randomized trials where available.

RESULTS

The lack of a uniformly applied definition of the poor responder and dearth of prospective randomized trials make data analysis difficult. Traditional GnRHa flare and long luteal phase protocols do not appear to be beneficial. Reduction of GnRHa doses, "stop" protocols, and microdose GnRHa flare regimes all appear to enhance outcomes, although the relative benefit of one approach over another has not been conclusively demonstrated. GnRHant does improve outcomes in this patient population, although, in general, pregnancy rates appear to be lower in comparison to microdose GnRHa flare regimes.

CONCLUSIONS

There is no one controlled ovarian hyperstimulation (COH) protocol which is best suited for all poor responders. Low dose GnRHa regimes appear to be most advantageous. Prediction of compromised response prior to cycle initiation by a thorough assessment of ovarian reserve as well as a careful review of past response should allow for selection of an appropriate COH protocol for each individual patient.

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.

Novel follicular-phase gonadotropin-releasing hormone antagonist stimulation protocol for in vitro fertilization in the poor responder

Poor responders continue to be vexing in infertility therapy. By using GnRH antagonists before ovarian stimulation, we demonstrate an improvement in oocyte, embryo, and zygote yield in patients with a prior poor response.

Gonadotropin-releasing hormone and reproductive medicine

The hypothalamic gonadotropin-releasing hormone (GnRH) is a key regulator of the reproductive system, mainly through its effects on pituitary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. Gonadotropin-releasing hormone analogues are modifications of the natural decapeptide, being either agonists (GnRHa) or antagonists. GnRHa may imitate the native hormone and induce an endogenous LH surge; however, sustained treatment with GnRHa results in complete refractoriness of LH and FSH production. This aspect of GnRHa action is the main application of the GnRHa in reproduction today. The hypogonadotropic hypogonadal state that results from the sustained treatment is the basis for additional applications of the GnRHa. The agonists appear to be effective, to some extent, for the treatment of endometriosis and were proved to be beneficial prior to surgery for fibroma uteri. GnRHa is used in assisted reproduction for both induction of an endogenous LH surge and for induction of ovulation, and its capacity to cause refractoriness of the pituitary may be used to avoid a premature LH surge. It is suggested that the GnRHa have a direct effect on ovarian steroidogenesis, which is independent of its action on the pituitary. This unwanted effect and other possible drawbacks of the agonists are thought to be eliminated with the use of the antagonists. The mechanism of action of these antagonists is through competitive blocking of the GnRH receptor, which results in a rapid but reversible suppression of gonadotropin secretion. As for GnRHa, GnRH antagonists have been proven effective to prevent the LH surge and to reduce the incidence of severe ovarian hyperstimulation syndrome in controlled ovarian stimulation cycles.

Evaluation and treatment of low responders in assisted reproductive technology: a challenge to meet

PURPOSE

To investigate the various methods of evaluation and treatment of patients with a low response to controlled ovarian hyperstimulation in assisted reproductive technologies (ART).

METHODS

Review and analysis of relevant studies published in the last decade, identified through the literature and Medline searches.

RESULTS

While a universally accepted definition for low responders is still lacking, these patients are reported to represent about 10% of the ART population. Several ovarian reserve screening techniques have been proposed; however, currently the best-characterized and most sensitive screening tools available are the basal day 3 serum follicle-stimulating hormone level and the clomiphene citrate challenge test. When abnormal, these tests allow physicians to counsel patients that their prognosis for conception is poor. Although the presence of a normal result does indicate better long-term chances for conception, on age-related decline in fecundity remains and patient age should still be considered when counseling patients with normal screening results. Several stimulation protocols have been applied in the low-response group with varying success. Recent studies show that the use of a minidose gonadotropin-releasing hormone-agonist protocol may result in significantly decreased cycle cancellations as well as increased clinical and ongoing pregnancies, and thus is proposed as a first-line therapy. Studies evaluating supplementary forms of treatment to the ovulation induction regimen show improved outcome when pretreating with oral contraceptives, whereas there seems to be no benefit from cotreatment with growth hormone or glucocorticoids. Blastocyst culture and transfer and assisted hatching in low responders are still under evaluation, whereas natural cycle in vitro fertilization may be used in cases of repeated failures as a last option before resorting to oocyte donation or adoption. Future possible forms of treatment like in vitro maturation of immature human oocytes, cytoplasm, and nuclear transfer currently are experimental in nature and their efficacy has still to be proven.

CONCLUSIONS

The evaluation and treatment of low responders in ART remains a challenge. Understanding of the underlying etiology and pathophysiology of this disorder may help the clinician to approach it successfully.

Evaluating strategies for improving ovarian response of the poor responder undergoing assisted reproductive techniques

OBJECTIVE

To assess the efficacy of various controlled ovarian hyperstimulation (COH) regimens in the prior poor-responder patient preparing for assisted reproductive techniques.

DESIGN

English-language literature review.

PATIENT(S)

Candidates for assisted reproductive techniques who had been defined as having a prior suboptimal response to standard COH regimens.

INTERVENTION(S)

A variety of regimes are reviewed, including increased gonadotropin doses, change of gonadotropins, adjunctive growth hormone (GH), luteal phase (long) GnRH agonist (GnRH-a) initiation, early follicular phase (flare) GnRH-a initiation, low-dose luteal phase (ultrashort) GnRH-a initiation, progestin pretreatment, and microdose flare GnRH-a initiation.

MAIN OUTCOME MEASURE(S)

Maximal serum E(2) levels, follicular development, dose, and duration of gonadotropin therapy, cycle cancellation rates, oocytes retrieved, embryos transferred, and clinical and ongoing pregnancy rates.

RESULT(S)

A lack of uniformity in definition of the poor responder and of prospective randomized trials make data interpretation somewhat difficult. Of the varied strategies proposed, those that seem to be more uniformly beneficial are microdose GnRH-a flare and late luteal phase initiation of a short course of low-dose GnRH-a discontinued before COH.

CONCLUSION(S)

No single regimen will benefit all poor responders. General acceptance of uniform definitions and performance of large-scale prospective randomized trials are critical. Development of a reliable precycle screen will allow effective differentiation among normal responders, poor responders, and those who will not conceive with their own oocytes.

Gonadotropin releasing hormone agonist protocols for pituitary desensitization in in vitro fertilization and gamete intrafallopian transfer cycles

BACKGROUND

Gonadotropin releasing hormone agonists (GnRHa) are used in assisted reproduction cycles to reversibly block pituitary function and prevent a luteinizing hormone surge. In the short and ultrashort protocols of GnRHa administration, injection of gonadotropins is commenced a few days after the start of GnRHa. In the long protocols (with GnRHa started either in the midluteal phase or in the early follicular phase) gonadotropin administration is delayed until pituitary desensitization has been achieved, usually 2-3 weeks.

OBJECTIVES

To conduct a systematic overview of available data comparing short or ultrashort and long GnRHa protocols for pituitary desensitization in in vitro fertilization (IVF) and gamete intra-fallopian transfer (GIFT) treatment cycles.

SEARCH STRATEGY

Search strategies included on-line searching of the MEDLINE and EMBASE data bases and the Cochrane Menstrual Disorders and Subfertility Group's Specialised Register from 1982 to 1998, and hand searching of bibliographies of relevant publications and reviews, and abstracts of scientific meetings.

SELECTION CRITERIA

Randomized trials of short or ultrashort versus long (follicular or luteal phase start) GnRHa protocols in IVF or GIFT treatment cycles.

DATA COLLECTION AND ANALYSIS

Data were extracted into 2 x 2 tables. For the primary outcome, clinical pregnancy per cycle started, the overall common odds ratio (OR) and the risk difference with 95% confidence interval (CI) were calculated after verifying the presence of homogeneity of treatment effect across all trials. The following subgroup comparisons were performed: ultrashort versus long protocols, short versus long protocols and, within each of these comparisons, subgroups of studies which used the long protocol with follicular phase start or the long protocol with luteal phase start. Secondary outcomes considered were clinical pregnancy per oocyte retrieval and per embryo transfer, spontaneous abortion, ongoing/delivered pregnancy per cycle started, number of ampoules of gonadotropin used, number of oocytes retrieved, and fertilization rate.

MAIN RESULTS

Twenty-six trials met the inclusion criteria. The common OR for clinical pregnancy per cycle started was 1.32 (95% CI, 1.10 - 1.57) in favour of the long GnRHa protocol. The studies were subgrouped, depending on whether, in the long protocol, the GnRHa was commenced in the follicular phase (8 trials) or luteal phase (16 trials). The respective ORs were 1.54 (95% CI, 1.11 - 2. 13) and 1.21 (95% CI, 0.98 - 1.51). After excluding the four trials using the ultrashort protocol, the OR for long versus short protocols (22 trials) was 1.27 (95% CI, 1.04 - 1.56). A comparison of long versus ultrashort protocols (4 trials) produced an OR of 1. 47 (95% CI, 1.02 - 2.12).

REVIEWER'S CONCLUSIONS

On the basis of clinical pregnancy rate per cycle started, this meta-analysis demonstrates the superiority of the long protocol over the short and ultrashort protocols for GnRHa use in IVF and GIFT cycles.

In vitro fertilization with low-dose clomiphene citrate stimulation in women who respond poorly to superovulation

PURPOSE

Our experience with IVF using low-dose clomiphene citrate for stimulation in "non-" and "poor" responders was reviewed and the treatment outcomes with the previous controlled ovarian stimulation cycles in which hMG and GnRH agonist were used were compared.

METHODS

The treatment outcome in 11 non- and 20 poor responders having 30 and 53 clomiphene citrate IVF treatment cycles, respectively, were compared with the treatment outcome in the previous long-protocol buserelin/hMG cycles.

RESULTS

The clinical pregnancy rates per oocyte collection achieved in the first clomiphene citrate cycle in non (9.1%)- and poor (10%) responders were comparable to those achieved by poor responders (11.9%) who had buserelin/hMG using the long protocol. Although the numbers were small, a similar pregnancy rate could still be achieved in poor responders up to the third attempt using clomiphene citrate.

CONCLUSIONS

IVF using long-protocol buserelin/hMG is more successful than using clomiphene citrate stimulation. However, this advantage may not be significant in those women with a previous poor response to buserelin/hMG. It is suggested that for such poor responders, three attempts of IVF in a clomiphene citrate cycle may offer a viable therapeutic alternative before reverting to more stressful, expensive, and time-consuming treatment.

High dosages of gonadotropins are associated with poor pregnancy outcomes after in vitro fertilization-embryo transfer

OBJECTIVE

To compare the pregnancy outcomes during IVF-ET when different dosages of hMG are used after follicular phase suppression with leuprolide acetate (LA).

DESIGN

Retrospective chart review.

SETTING

Hospital-based IVF-ET program.

PATIENTS

From January 1990 to December 1992, 264 cycles reached ET after LA downregulation and gonadotropin stimulation.

RESULTS

Higher doses of gonadotropins, as measured by both average daily dose and total dose per cycle, were associated with lower clinical pregnancy rates. This effect was independent of age, basal FSH level, endometrial thickness, maximal E2 levels, number of eggs retrieved, and embryos transferred.

CONCLUSION

High dosages of exogenous gonadotropins are associated with lower pregnancy rates in IVF-ET.