The evaluation of a new 7-day gonadotropin-releasing hormone agonist protocol in the controlled ovarian hyperstimulation for in vitro fertilization

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.

Evidence of improving quality of reporting of randomized controlled trials in subfertility

BACKGROUND

The quality of randomized controlled trials (RCTs) in subfertility and their suitability for inclusion in meta-analyses have been assessed in the past and found to be insufficient. Our aim was to assess whether this quality has improved over time, particularly since the publication of the Consolidated Standards of Reporting Trials (CONSORT) statement, and to assess what proportion of trials could be included in the meta-analyses of pregnancy outcomes such as those included in Cochrane Reviews.

METHODS

A selection of subfertility trials published in 1990, 1996 and 2002 was collected from the Cochrane Menstrual Disorder and Subfertility Group (MDSG) database. Only trials published in English as full journal articles, claiming to be randomized and reporting on pregnancy outcomes, were included.

RESULTS

One hundred and sixty-four trials met our inclusion criteria. Twenty-four (15%) were found not to be randomized, despite claims, and only 10 trials (6%) provided adequate details on the methods of randomization and allocation concealment. Of these, only three had sufficient details extractable to allow for an intention-to-treat analysis of the outcome 'live birth'.

CONCLUSIONS

Although an improvement in some subfertility-specific issues was observed, the quality of reporting of RCTs still needs to improve to make them suitable for inclusion in meta-analyses such as those in the Cochrane Library.

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.