In vitro fertilisation for unexplained subfertility.

BACKGROUND: In vitro fertilisation (IVF) is a treatment for unexplained subfertility but is invasive, expensive, and associated with risks. OBJECTIVES: To evaluate the effectiveness and safety of IVF versus expectant management, unstimulated intrauterine insemination (IUI), and IUI with ovarian stimulation using gonadotropins, clomiphene citrate (CC), or letrozole in improving pregnancy outcomes. SEARCH METHODS: We searched following databases from inception to November 2021, with no language restriction: Cochrane Gynaecology and Fertility Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL. We searched reference lists of articles and conference abstracts. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing effectiveness of IVF for unexplained subfertility with expectant management, unstimulated IUI, and stimulated IUI. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods. MAIN RESULTS: IVF versus expectant management (two RCTs) We are uncertain whether IVF improves live birth rate (LBR) and clinical pregnancy rate (CPR) compared to expectant management (odds ratio (OR) 22.0, 95% confidence interval (CI) 2.56 to 189.37; 1 RCT; 51 women; very low-quality evidence; OR 3.24, 95% CI 1.07 to 9.8; 2 RCTs; 86 women; I2 = 80%; very low-quality evidence). Adverse effects were not reported. Assuming 4% LBR and 12% CPR with expectant management, these would be 8.8% to 9% and 13% to 58% with IVF. IVF versus unstimulated IUI (two RCTs) IVF may improve LBR compared to unstimulated IUI (OR 2.47, 95% CI 1.19 to 5.12; 2 RCTs; 156 women; I2 = 60%; low-quality evidence). We are uncertain whether there is a difference between IVF and IUI for multiple pregnancy rate (MPR) (OR 1.03, 95% CI 0.04 to 27.29; 1 RCT; 43 women; very low-quality evidence) and miscarriage rate (OR 1.72, 95% CI 0.14 to 21.25; 1 RCT; 43 women; very low-quality evidence). No study reported ovarian hyperstimulation syndrome (OHSS). Assuming 16% LBR, 3% MPR, and 6% miscarriage rate with unstimulated IUI, these outcomes would be 18.5% to 49%, 0.1% to 46%, and 0.9% to 58% with IVF. IVF versus IUI + ovarian stimulation with gonadotropins (6 RCTs), CC (1 RCT), or letrozole (no RCTs) Stratified analysis was based on pretreatment status. Treatment-naive women There may be little or no difference in LBR between IVF and IUI + gonadotropins (1 IVF to 2 to 3 IUI cycles: OR 1.19, 95% CI 0.87 to 1.61; 3 RCTs; 731 women; I2 = 0%; low-quality evidence; 1 IVF to 1 IUI cycle: OR 1.63, 95% CI 0.91 to 2.92; 2 RCTs; 221 women; I2 = 54%; low-quality evidence); or between IVF and IUI + CC (OR 2.51, 95% CI 0.96 to 6.55; 1 RCT; 103 women; low-quality evidence). Assuming 42% LBR with IUI + gonadotropins (1 IVF to 2 to 3 IUI cycles) and 26% LBR with IUI + gonadotropins (1 IVF to 1 IUI cycle), LBR would be 39% to 54% and 24% to 51% with IVF. Assuming 15% LBR with IUI + CC, LBR would be 15% to 54% with IVF. There may be little or no difference in CPR between IVF and IUI + gonadotropins (1 IVF to 2 to 3 IUI cycles: OR 1.17, 95% CI 0.85 to 1.59; 3 RCTs; 731 women; I2 = 0%; low-quality evidence; 1 IVF to 1 IUI cycle: OR 4.59, 95% CI 1.86 to 11.35; 1 RCT; 103 women; low-quality evidence); or between IVF and IUI + CC (OR 3.58, 95% CI 1.51 to 8.49; 1 RCT; 103 women; low-quality evidence). Assuming 48% CPR with IUI + gonadotropins (1 IVF to 2 to 3 IUI cycles) and 17% with IUI + gonadotropins (1 IVF to 1 IUI cycle), CPR would be 44% to 60% and 28% to 70% with IVF. Assuming 21% CPR with IUI + CC, CPR would be 29% to 69% with IVF. There may be little or no difference in multiple pregnancy rate (MPR) between IVF and IUI + gonadotropins (1 IVF to 2 to 3 IUI cycles: OR 0.82, 95% CI 0.38 to 1.77; 3 RCTs; 731 women; I2 = 0%; low-quality evidence; 1 IVF to 1 IUI cycle: OR 0.76, 95% CI 0.36 to 1.58; 2 RCTs; 221 women; I2 = 0%; low-quality evidence); or between IVF and IUI + CC (OR 0.64, 95% CI 0.17 to 2.41; 1 RCT; 102 women; low-quality evidence). We are uncertain if there is a difference in OHSS between IVF and IUI + gonadotropins with 1 IVF to 2 to 3 IUI cycles (OR 6.86, 95% CI 0.35 to 134.59; 1 RCT; 207 women; very low-quality evidence); and there may be little or no difference in OHSS with 1 IVF to 1 IUI cycle (OR 1.22, 95% CI 0.36 to 4.16; 2 RCTs; 221 women; I2 = 0%; low-quality evidence). There may be little or no difference between IVF and IUI + CC (OR 1.53, 95% CI 0.24 to 9.57; 1 RCT; 102 women; low-quality evidence). We are uncertain if there is a difference in miscarriage rate between IVF and IUI + gonadotropins with 1 IVF to 2 to 3 IUI cycles (OR 0.31, 95% CI 0.03 to 3.04; 1 RCT; 207 women; very low-quality evidence); and there may be little or no difference with 1 IVF to 1 IUI cycle (OR 1.16, 95% CI 0.44 to 3.02; 1 RCT; 103 women; low-quality evidence). There may be little or no difference between IVF and IUI + CC (OR 1.48, 95% CI 0.54 to 4.05; 1 RCT; 102 women; low-quality evidence). In women pretreated with IUI + CC IVF may improve LBR compared with IUI + gonadotropins (OR 3.90, 95% CI 2.32 to 6.57; 1 RCT; 280 women; low-quality evidence). Assuming 22% LBR with IUI + gonadotropins, LBR would be 39% to 65% with IVF. IVF may improve CPR compared with IUI + gonadotropins (OR 14.13, 95% CI 7.57 to 26.38; 1 RCT; 280 women; low-quality evidence). Assuming 30% CPR with IUI + gonadotropins, CPR would be 76% to 92% with IVF. AUTHORS' CONCLUSIONS: IVF may improve LBR over unstimulated IUI. Data should be interpreted with caution as overall evidence quality was low.

Glucocorticoid supplementation during ovarian stimulation for IVF or ICSI.

BACKGROUND: Ovarian response to stimulation during in-vitro fertilisation (IVF) and intra-cytoplasmic sperm injection (ICSI) plays an important role in determining live birth rates. Adjuvant treatments during ovarian stimulation that have different modes of action have been used to improve ovarian response to stimulation and outcome of IVF. Glucocorticoids (GCs) are a class of steroid hormones that have been used either alone or in combination with other stimulatory regimens in order to improve folliculogenesis and pregnancy rates. However, considerable uncertainty remains over whether administration of glucocorticoid during ovarian stimulation until oocyte recovery is superior to no glucocorticoid in improving live birth rates in women undergoing IVF/ICSI. OBJECTIVES: To determine the safety and effectiveness of systemic glucocorticoids during ovarian stimulation for IVF and ICSI cycles. SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Studies Online (CRSO), MEDLINE, Embase, CINAHL and PsycINFO from inception to 10 October 2016. We handsearched reference lists of articles, trial registers and relevant conference proceedings and contacted researchers in the field. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing adjuvant treatment with systemic glucocorticoids during ovarian stimulation for IVF or ICSI cycles versus no adjuvant treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed risk of bias and extracted the data. Our primary outcome was live birth. Secondary outcomes included clinical pregnancy, multiple pregnancy, miscarriage, ovarian hyperstimulation syndrome (OHSS) and side-effects. We calculated odds ratios (ORs) with 95% confidence intervals (CIs) and pooled the data using a fixed-effect model. The quality of the evidence was assessed using GRADE methods. MAIN RESULTS: Four RCTs were included in the review (416 women). The trials compared glucocorticoid supplementation during IVF stimulation versus placebo. Two of the studies had data in a form that we could not enter into analysis, so results include data from only two trials (310) women. For the outcome of live birth, data were available for only 212 women, as the larger study had data available from only one study centre.One of the studies gave inadequate description of randomisation methods, but the other was at low risk of bias in all domains. The evidence was rated as low or very low quality for all outcomes, mainly due to imprecision, with low sample sizes and few events.There was insufficient evidence to determine whether there was any difference between the groups in live birth rate (OR 1.08, 95% CI 0.45 to 2.58; 2 RCTs, n = 212, I2 = 0%, low-quality evidence). Our findings suggest that if the chance of live birth with placebo is assumed to be 15%, the chance following supplementation would be between 7% and 31%. There was no conclusive evidence of a difference in the clinical pregnancy rate (OR 1.69, 95% CI 0.98 to 2.90; 2 RCTs, n = 310, I2 = 0%, low-quality evidence).The evidence suggests that if the chance of clinical pregnancy with placebo is assumed to be 24%, the chance following treatment with glucocorticoid supplementation would be between 23% and 47%. There was also insufficient evidence to determine whether there was any difference between the groups in multiple-pregnancy rate (OR 3.32 , 95% CI 0.12 to 91.60; 1 RCT , n = 20, very low-quality evidence) or miscarriage rate (OR 1.00, 95% CI 0.05 to 18.57; 1 RCT, n = 20, very low-quality evidence). Neither of the studies reported OHSS or side-effects. AUTHORS' CONCLUSIONS: The safety and effectiveness of glucocorticoid administration in women undergoing controlled ovarian hyperstimulation for IVF/ICSI cycles (until the day of oocyte retrieval) is unclear due to the small number of studies and low event rates. Whilst glucocorticoids possible increase the clinical pregnancy rate, there may be little or no impact on live birth rate. More research is needed.

In vitro fertilisation for unexplained subfertility.

BACKGROUND: One-third of subfertile couples have no identifiable cause for their inability to conceive. In vitro fertilisation (IVF) is a widely accepted treatment for this condition; however, this treatment is invasive and expensive and is associated with risks. OBJECTIVES: To evaluate the effectiveness and safety of IVF compared with expectant management, unstimulated intrauterine insemination (IUI) or intrauterine insemination along with ovarian stimulation with gonadotropins (IUI + gonadotropins) or clomiphene (IUI + CC) or letrozole (IUI + letrozole) in improving pregnancy outcomes. SEARCH METHODS: This review has drawn on the search strategy developed by the Cochrane Menstrual Disorders and Subfertility Group. We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (searched May 2015), the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, first quarter), MEDLINE (1946 to May 2015), EMBASE (1985 to May 2015), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (May 2015) and reference lists of articles. We searched the following trial registries: clinicaltrials.gov (http://www.clinicaltrials.gov) and the World Health Organization International Trials Registry Platform search portal (http://www.who.int/trialsearch/Default.aspx). We searched the Web of Science (http://wokinfo.com/) as another source of trials and conference abstracts, OpenGrey (http://www.opengrey.eu/) for unpublished literature from Europe and the Latin American Caribbean Health Sciences Literature (LILACS) database (http://regional.bvsalud.org/php/index.php?lang=en). Moreover, we handsearched relevant conference proceedings and contacted study authors to ask about additional publications.Two review authors independently assessed trial eligibility, extracted data and assessed risk of bias. The primary review outcome was cumulative live birth rate. Multiple pregnancy and other adverse effects were secondary outcomes. We combined data to calculate pooled risk ratios (RRs) and 95% confidence intervals (CIs). We assessed statistical heterogeneity by using the I(2) statistic. We assessed the overall quality of evidence for the main comparisons using Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methods. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in which the effectiveness of IVF in couples with unexplained subfertility was compared with that of other treatments, including expectant management, unstimulated IUI and stimulated IUI using gonadotropins or clomiphene or letrozole.Live birth rate (LBR) per woman was the primary outcome. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the eligibility and quality of trials and evaluated the quality of the evidence by using GRADE criteria. MAIN RESULTS: IVF versus expectant management (two RCTs):Live birth rate per woman was higher with IVF than with expectant management (odds ratio (OR) 22.00, 95% confidence interval (CI) 2.56 to 189.37, one RCT, 51 women, very low quality evidence). Multiple pregnancy rates (MPRs), ovarian hyperstimulation syndrome (OHSS) and miscarriage were not reported. IVF versus unstimulated IUI (two RCTs):Live birth rate was higher with IVF than with unstimulated IUI (OR 2.47, 95% CI 1.19 to 5.12, two RCTs, 156 women, I(2) = 60%, low quality evidence). There was no evidence of a difference between the groups in multiple pregnancy rates (OR 1.03, 95% CI 0.04 to 27.29, one RCT, 43 women, very low quality evidence) IVF versus IUI + ovarian stimulation with gonadotropins (three RCTs) or clomiphene (one RCT) or letrozole (no RCTs):Data from these trials could not be pooled because of high statistical heterogeneity (I(2) = 93.3%). Heterogeneity was eliminated when studies were stratified by pretreatment status.In trials comparing IVF versus IUI + gonadotropins among treatment-naive women, there was no conclusive evidence of a difference between the groups in live birth rates (OR 1.27, 95% CI 0.94 to 1.73, four RCTs, 745 women, I(2) = 8.0%, moderate-quality evidence). In women pretreated with IUI + clomiphene, a higher live birth rate was reported among those who underwent IVF than those given IUI + gonadotropins (OR 3.90, 95% CI 2.32 to 6.57, one RCT, 280 women, moderate-quality evidence).There was no conclusive evidence of a difference in live birth rates between IVF and IUI + CC in treatment-naive women (OR 2.51, 95% CI 0.96 to 6.55, one RCT, 103 women, low quality evidence).In treatment-naive women, there was no evidence of a difference in rates of multiple pregnancy between women who underwent IVF and those who received IUI + gonadotropins (OR 0.79, 95% CI 0.45 to 1.39, four RCTs, 745 women, I(2) = 0%, moderate quality evidence). There was no evidence of a difference in MPRs between women who underwent IVF compared with those given IUI + CC (OR 1.02, 95% CI 0.20 to 5.31, one RCT, 103 women, low-quality evidence).There was no evidence of a difference in ovarian hyperstimulation syndrome rate between treatment-naive women who underwent IVF and those given IUI + gonadotropins (OR 1.23, 95% CI 0.36 to 4.14, two RCTs, 221 women, low quality evidence). There was no evidence of a difference in OHSS rates between groups receiving IVF versus those receiving IUI + CC (OR 1.02, 95% CI 0.20 to 5.31, one RCT, 103 women, low-quality evidence).In treatment naive women, there was no evidence of a difference in miscarriage rates between IVF and IUI + CC (OR 1.16, 95% CI 0.44 to 3.02, one RCT, 103 women, low-quality evidence), nor between women treated with IVF versus those receiving IUI+ gonadotropins (OR 1.16, 95% CI 0.44 to 3.02, one RCT, 103 women).No studies compared IVF with IUI + letrozole.The quality of the evidence ranged from very low to moderate. The main limitation was serious imprecision resulting from small study numbers and low event rates. AUTHORS' CONCLUSIONS: IVF may be associated with higher live birth rates than expectant management, but there is insufficient evidence to draw firm conclusions. IVF may also be associated with higher live birth rates than unstimulated IUI. In women pretreated with clomiphene + IUI, IVF appears to be associated with higher birth rates than IUI + gonadotropins. However in women who are treatment-naive there is no conclusive evidence of a difference in live birth rates between IVF and IUI + gonadotropins or between IVF and IUI + clomiphene. Adverse events associated with these interventions could not be adequately assessed owing to lack of evidence.

Number of embryos for transfer following in vitro fertilisation or intra-cytoplasmic sperm injection.

BACKGROUND: Multiple embryo transfer during in vitro fertilisation (IVF) increases multiple pregnancy rates causing maternal and perinatal morbidity. Single embryo transfer is now being seriously considered as a means of minimising the risk of multiple pregnancy. However, this needs to be balanced against the risk of jeopardising the overall live birth rate. OBJECTIVES: To evaluate the effectiveness and safety of different policies for the number of embryos transferred in couples who undergo assisted reproductive technology (ART). SEARCH METHODS: We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE, from inception to July 2013. We handsearched reference lists of articles, trial registers and relevant conference proceedings and contacted researchers in the field. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing different policies for the number of embryos transferred following IVF or intra-cytoplasmic sperm injection (ICSI) in subfertile women. Studies of fresh or frozen and thawed transfer of one, two, three or four embryos at cleavage or blastocyst stage were eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial eligibility and risk of bias and extracted the data. The overall quality of the evidence was graded in a summary of findings table. MAIN RESULTS: Fourteen RCTs were included in the review (2165 women). Thirteen compared cleavage-stage transfers (2017 women) and two compared blastocyst transfers (148 women): one study compared both. No studies compared repeated multiple versus repeated single embryo transfer (SET). DET versus repeated SETDET was compared with repeated SET in three studies of cleavage-stage transfer. In these studies the SET group received either two cycles of fresh SET (one study) or one cycle of fresh SET followed by one frozen SET in a natural or hormone-stimulated cycle (two studies). When these three studies were pooled, the cumulative live birth rate after one cycle of DET was not significantly different from the rate after repeated SET (OR 1.22, 95% CI 0.92 to 1.62, three studies, n=811, I(2)=0%, low quality evidence). This suggests that for a woman with a 40% chance of live birth following a single cycle of DET, the chance following repeated SET would be between 30% and 42%. The multiple pregnancy rate was significantly higher in the DET group (OR 30.54, 95% CI 7.46 to 124.95, three RCTs, n = 811, I(2) = 23%, low quality evidence), suggesting that for a woman with a 15% risk of multiple pregnancy following a single cycle of DET, the risk following repeated SET would be between 0% and 2%. Single-cycle DET versus single-cycle SETA single cycle of DET was compared with a single cycle of SET in 10 studies, nine comparing cleavage-stage transfers and two comparing blastocyst-stage transfers. When all studies were pooled the live birth rate was significantly higher in the DET group (OR 2.07, 95% CI 1.68 to 2.57, nine studies, n = 1564, I(2) = 0%, high quality evidence). This suggests that for a woman with a 40% chance of live birth following a single cycle of DET, the chance following a single cycle of SET would be between 22% and 30%. The multiple pregnancy rate was also significantly higher in the DET group (OR 8.47, 95% CI 4.97 to 14.43, 10 studies, n = 1612, I(2) = 45%, high quality evidence), suggesting that for a woman with a 15% risk of multiple pregnancy following a single cycle of DET, the risk following a single cycle of SET would be between 1% and 4%. The heterogeneity for this analysis was attributable to a study with a high rate of cross-over between treatment arms. Other comparisons Other fresh cycle comparisons were evaluated in three studies which compared DET versus transfer of three or four embryos. Live birth rates did not differ significantly between the groups for any comparison, but there was a significantly lower multiple pregnancy rate in the DET group than in the three embryo transfer (TET) group (OR 0.36, 95% CI 0.13 to 0.99, two studies, n = 343, I(2) = 0%). AUTHORS' CONCLUSIONS: In a single fresh IVF cycle, single embryo transfer is associated with a lower live birth rate than double embryo transfer. However, there is no evidence of a significant difference in the cumulative live birth rate when a single cycle of double embryo transfer is compared with repeated SET (either two cycles of fresh SET or one cycle of fresh SET followed by one frozen SET in a natural or hormone-stimulated cycle). Single embryo transfer is associated with much lower rates of multiple pregnancy than other embryo transfer policies. A policy of repeated SET may minimise the risk of multiple pregnancy in couples undergoing ART without substantially reducing the likelihood of achieving a live birth. Most of the evidence currently available concerns younger women with a good prognosis.

In vitro fertilisation for unexplained subfertility.

BACKGROUND: In vitro fertilisation (IVF) is a widely accepted treatment for unexplained infertility (NICE 2004), which affects up to a third of all infertile couples. With estimated live birth rates (LBRs) per cycle varying from 33.1% in women aged under 35 years down to 12.5% in women aged between 40 and 42 years (HFEA 2011), its effectiveness has not been rigorously evaluated in comparison with other treatments. With increasing awareness of the role of expectant management, less-invasive procedures such as intrauterine insemination (IUI), and concerns about multiple pregnancies and costs associated with IVF, it is important to evaluate the effectiveness of IVF against other treatment options in couples with unexplained infertility. OBJECTIVES: To evaluate the effectiveness and safety of IVF compared to expectant management, clomiphene citrate, IUI alone and intrauterine insemination plus controlled ovarian stimulation (IUI+SO). SEARCH METHODS: Cochrane Menstrual Disorders and Subfertility Group Trials Register (searched July 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, first quarter), MEDLINE (1970 to July 2011), EMBASE (1985 to July 2011) and reference lists of articles were searched. Relevant conference proceedings were handsearched. Authors were contacted. SELECTION CRITERIA: Randomised controlled trials (RCTs) were included. LBR per woman was the primary outcome. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility and quality of trials. MAIN RESULTS: Six RCTs were included in the final analysis. LBR per woman was significantly higher with IVF (45.8%) than expectant management (3.7%) (odds ratio (OR) 22.00, 95% confidence interval (CI) 2.56 to 189.37, 1 RCT, 51 women). There were no comparative data for clomiphene citrate. There was no evidence of a significant difference in LBR between IVF and IUI alone (OR 1.96, 95% CI 0.88 to 4.36, 1 RCT, 113 women), 40.7% with IVF versus 25.9% with IUI. In studies comparing IVF versus IUI+SO, LBR per woman did not differ significantly between the groups among treatment-naive women (OR 1.09, 95% CI 0.74 to 1.59, 2 RCTs, 234 women) but was significantly higher in a large RCT of women pretreated with IUI + clomiphene citrate (OR 2.66, 95% CI 1.94 to 3.63, 1 RCT, 341 women). These three studies could not be pooled due to high heterogeneity (I(2) = 84%). There was no evidence of a significant difference in multiple pregnancy rate (MPR) or ovarian hyperstimulation syndrome (OHSS) between the two treatments (OR 0.64, 95% CI 0.31 to 1.29, 3 RCTs, 351 women; OR 1.53, 95% CI 0.25 to 9.49, 1 RCT, 118 women, respectively). AUTHORS' CONCLUSIONS: IVF may be more effective than IUI+SO. Due to paucity of data from RCTs the effectiveness of IVF for unexplained infertility relative to expectant management, clomiphene citrate and IUI alone remains unproven. Adverse events and the costs associated with these interventions have not been adequately assessed.

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

BACKGROUND: The success of in-vitro fertilisation (IVF) 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 IVF. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials (MDSG) (5/1/2009), the Cochrane Central Register of Controlled trials (CENTRAL) (4th Quarter 2008), MEDLINE (1950 to November week 3 2008), EMBASE (1980 to 2008 week 52) 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 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 reviewers independently scanned the abstracts, identified relevant papers, assessed trial quality and extracted relevant data for inclusion. 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: The new search identified fifteen trials. Three trials were eligible for inclusion. Ten trials involving eight different comparison groups have been included. Only one trial reported live birth rates.The number of oocytes retrieved were significantly less in the conventional GnRHa long protocol compared to stop protocol and GnRH antagonist protocol.Total dose of gonadotrophins used was significantly higher in the GnRHa long protocol group compared to the Stop protocol and GnRH antagonist groups.Cancellation rates were significantly higher in the GnRHa flare up group compared to the GnRHa long protocol group.None of the studies reported a difference in the miscarriage and ectopic pregnancy rates. AUTHORS' CONCLUSIONS: There is insufficient evidence to support the routine use of any particular intervention either for pituitary down regulation, 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.

Number of embryos for transfer following in-vitro fertilisation or intra-cytoplasmic sperm injection.

BACKGROUND: Multiple embryo transfer during IVF has increased multiple pregnancy rates (MPR) causing maternal and perinatal morbidity. Elective single embryo transfer (SET) is now being considered as an effective means of reducing this iatrogenic complication. OBJECTIVES: To determine in couples undergoing IVF/ICSI (intra-cytoplasmic sperm injection) whether:(1) elective transfer of two embryos improves the probability of livebirth compared with:(a) elective single embryo transfer,(b) three embryo transfer (TET) or(c) four embryo transfer (FET).(2) elective transfer of three embryos improves the probability of livebirth compared with:(a) elective single embryo transfer, or(b) elective four embryo transfer. SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group's trials register (searched March 2008), the Cochrane Central Register of Controlled Trials (Cochrane Library, Issue 1, 2008), MEDLINE (1970 to 2008), EMBASE (1985 to 2008) and reference lists of articles. Relevant conference proceedings were hand-searched and researchers in the field contacted. SELECTION CRITERIA: Randomised controlled trials were included. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed eligibility and quality of trials. MAIN RESULTS: For the update in 2008 five trials compared DET with SET. DET versus TET and DET versus FET were evaluated in a single small trial each. The difference in cumulative livebirth rates (CLBR) after DET and those after SET followed by transfer of a single frozen thawed embryo (1FZET) was not statistically significant (OR 0.81, 95% CI 0.59 to 1.11; p=0.18). There was no statistically significant difference in CLBR after a single fresh cycle of DET versus two fresh cycles of SET (OR 1.23, 95% CI 0.56 to 2.69, p= 0.60 ). The live birth rate (LBR) per woman in a single fresh treatment was higher following DET than SET (OR 2.10, 95% CI 1.65 to 2.66, p<0.00001). The MPR was lower following SET (OR 0.04, 95% CI 0.01 to 0.11; p< 0.00001). The CLBR following two fresh cycles of DET versus two fresh cycles of TET (OR 0.77, 95%CI 0.22 to 2.65, p=0.67) and CLBR after three fresh cycles of DET versus three fresh cycles of TET showed no statistically significant differences (OR 0.77, 95% CI 0.24 to 2.52; p=0.67). There were no statistically significant differences between DET and TET in terms of LBR (OR 0.40, 95%CI 0.09 to 1.85; p=0.24) and MPR (OR 0.17, 95%CI 0.01 to 3.85; p= 0.27). DET led to lower LBR than FET but the difference was not statistically significant (OR 0.35, 95% CI 0.11 to 1.05; p = 0.06). AUTHORS' CONCLUSIONS: In a single fresh IVF cycle, SET is associated with a lower LBR than DET. However there is no significant difference in CLBR following SET+ 1FZET and the LBR following a single cycle of DET. MPR are lowered following SET compared with other transfer policies. There are insufficient data on the outcome of two versus three and four embryo transfer policies.

Surgery for tubal infertility.

BACKGROUND: Tubal surgery is a widely accepted treatment for tubal infertility. Estimated livebirth rates after surgery range from 9% for women with severe tubal disease to 69% for those with mild disease, however, its effectiveness has not been rigorously evaluated in comparison with other treatments such as in vitro fertilisation (IVF) and expectant management (no treatment). Livebirth rates have not been adequately assessed in relation to the severity of tubal damage. It is important to determine the effectiveness of surgery against other treatment options in women with tubal infertility because of concerns about adverse outcomes, intra-operative complications and the costs associated with tubal surgery. OBJECTIVES: The aim of this review was to determine whether surgery improves the probability of livebirth compared with expectant management or IVF in the context of tubal infertility (regardless of grade of severity). SEARCH STRATEGY: We searched the Cochrane Menstrual Disorders and Subfertility Group's trials register (searched August 2007), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue, 2007), MEDLINE (1970 to August 2007), EMBASE (1985 to August 2007) and reference lists of articles. We also handsearched relevant conference proceedings and contacted researchers in the field. SELECTION CRITERIA: Only randomised controlled trials were considered eligible, with livebirth rate per woman as the primary outcome of interest. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility and quality of trials. MAIN RESULTS: No suitable randomised controlled trials were identified. AUTHORS' CONCLUSIONS: Any effect of tubal surgery relative to expectant management and IVF in terms of livebirth rates for women with tubal infertility remains unknown. Large trials with adequate power are warranted to establish the effectiveness of surgery in these women. Future trials should not only report livebirth rates per woman, but also compare adverse effects and costs of the treatments as outcomes. Factors that have a major effect on these outcomes, such as fertility treatment, female partner's age, duration of infertility, and previous pregnancy history should be considered. Livebirth rates in relation to the severity of tubal damage, and different techniques used for tubal repair including microsurgery and laparoscopic methods should also be reported.

Number of embryos for transfer after IVF and ICSI: a Cochrane review.

BACKGROUND: The most common complication of IVF is multiple pregnancy, which occurs in 25% of pregnancies following the transfer of two embryos. Single embryo transfer can minimize twin pregnancies but could also lower live birth rates. Our aim was to perform a systematic review of randomized trials to determine the effectiveness of single versus double embryo transfer. METHODS: Cochrane Collaboration review methods were followed. Randomized controlled trials comparing single and double embryo transfers were identified by searching Medline, EMBASE and the Cochrane register of controlled trials. Contents of specialist journals and proceedings from meetings of relevant societies were hand searched. Data were pooled with Rev Man software using the Peto-modified Mantel-Hanzel method. RESULTS: Pooled results from four trials indicate that although double embryo transfer leads to a higher live birth rate per woman [odds ratio (OR) 1.94, 95% confidence interval (CI) 1.47-2.55] in a fresh IVF cycle, comparable results are obtained by subsequent transfer of a frozen embryo (OR 1.19, 95% CI 0.87-1.62). The multiple pregnancy rate is significantly higher (OR 62.83, 95% CI 8.52-463.57) after double embryo transfer. CONCLUSIONS: Single embryo transfer significantly reduces the risk of multiple pregnancy, but also decreases the chance of live birth in a fresh IVF cycle. Subsequent replacement of a single frozen embryo achieves a live birth rate comparable with double embryo transfer.

The effectiveness of IVF in unexplained infertility: a systematic Cochrane review. 2002,.

BACKGROUND: IVF is an accepted treatment for unexplained infertility. The objective of this review was to determine whether, for unexplained infertility, IVF improves the probability of live birth compared with: (i) expectant management; (ii) clomiphene citrate (CC); (iii) intrauterine insemination (IUI); (iv) IUI with controlled ovarian stimulation; and (v) gamete intra-Fallopian transfer (GIFT). METHODS: This was based on a Cochrane review. Randomized controlled trials (RCTs) which compared the effectiveness of IVF with expectant management, CC, IUI with or without controlled ovarian stimulation and GIFT were included. Patients included couples with unexplained infertility. Live birth rate per woman/couple was the main outcome measure. RESULTS: Nine RCT were identified. Five RCTs were included in the final meta-analysis. There were no comparative data for CC and live birth rates for expectant management or GIFT. There was no significant difference in clinical pregnancy rates between IVF and expectant management. There was no evidence of a difference in live birth rates between IVF and IUI either without (OR 1.96, 95% CI 0.88 to 4.36) or with (OR 1.15, 95% CI 0.55 to 2.42) ovarian stimulation. Clinical pregnancy rates with IVF were significantly higher compared with GIFT (OR 2.14, 95% CI 1.08 to 4.22) as were the multiple pregnancy rates (OR 6.25, 95% CI 1.70 to 23.00). Clinical heterogeneity was present among the studies. There was no evidence of statistical heterogeneity. CONCLUSIONS: The effectiveness of IVF in unexplained infertility remains unproven. Larger trials with adequate power are warranted.