Two cycles with single embryo transfer versus one cycle with double embryo transfer: a randomized controlled trial

Zhang

et al. 2011

Objective To evaluate the relationship between different hCG priming-to-oocyte retrieval intervals and assisted reproductive technology (ART) outcome. Methods We systematically searched PubMed, EMBASE, the Cochrane Library, Science Citation Index, Chinese biomedicine (CBM) literature database, and Chinese Journal Full-text Database for randomized controlled trials (RCTs) published up to November 2010. Data was extracted from the studies by two independent reviewers. Statistical analysis was performed with Cochrane Collaboration's Review Manager (RevMan) 5.0.2. From extracted data, Risk Ratio (RR) with 95% confidence interval (CI) was calculated. Results 5 RCTs totaling 895 participants were included. Oocyte maturation rate was higher in the long interval group compared with short interval group (RR, 0.67; 95% CI, 0.62-0.73). There were no significant difference between the two groups with regard to fertilization rate (RR, 0.99; 95% CI, 0.94-1.04), implantation rate (RR, 0.91; 95% CI, 0.40-2.04), and pregnancy rate (RR, 0.79; 95% CI, 0.58-1.08). Conclusion The percentage of mature (MII) oocytes can be increased by prolonging the interval between hCG priming and oocyte retrieval. The prolonged interval could not increase the fertilization rate, implantation rate, and pregnancy rate. Although there was evidence to confirm the results, they still need to be confirmed by large-sample, multicenter, randomized controlled trials. The time interval dependent mechanisms responsible for ART performance need to be elucidated.

Section: Discussionmentioning

confidence: 99%

The time interval between hCG priming and oocyte retrieval in ART program: a meta-analysis

Zhang

et al. 2011

“…However it has been reported that, even though eSET elevates the chance of delivering a healthy baby compared to double embryo transfer (DET) in cleavage stage embryo [7], eSET results in significantly decreased pregnancy and delivery rates per embryo transfer [8,9]. In contrast to these results, it has been reported that the clinical outcomes of elective single blastocyst embryo transfer (eSBET) are similar to those of double blastocyst embryo transfer (DBET) on day 5 [10].…”

Section: Introductionmentioning

confidence: 99%

Clinical outcomes of elective single morula embryo transfer versus elective single blastocyst embryo transfer in IVF-ET

Kang

Lee

Jeong

et al. 2012

Purpose To compare the clinical outcomes of elective single morula embryo transfer (eSMET) versus elective single blastocyst embryo transfer (eSBET) in selected patients. Methods This study was a retrospective study which analyzed for 271 cycles in women under 37 years of age who are undergoing their first or second trial of in vitro fertilization-embryo transfer (IVF-ET) from January 2008 to December 2009. The eSMET was performed on day 4 (n0130) and the eSBET was conducted on day 5 (n0141). Results The clinical pregnancy rate (51.5% vs. 51.8%, p0 0.97), implantation rate (52.3% vs. 52.5%, p00.98), and live birth rate (39.2% vs. 44.7%, p00.36) were similar in the eSMET and eSBET groups, respectively. The miscarriage rate of the eSMET group (23.9%) was slightly higher than that of the eSBET group (13.7%) (p00.12), without reaching statistical significance. There was only one case of monozygotic twin pregnancy in each group. ConclusionsThe clinical outcomes of day 4 eSMET were comparable to those of day 5 eSBET. Therefore, day 4 eSMET is a viable option or an alternative to day 5 eSBET, with no difference in success rates.

“…Randomised studies [7,14,[20][21][22] comparing 1 or 2 embryo transfer on a population at risk of multiple pregnancies (maternal age <36 or 34 years, number of high quality embryos) shows a decrease of pregnancy rate in fresh cycles. Therefore thawing frozen embryos allows the re-establishing of pregnancy rate which was otherwise decreased.…”

Section: Discussionmentioning

confidence: 99%

Contribution of cryopreservation in a mandatory SET policy: analysis of 5 years of application of law in an academic IVF center

Salame

Devreker

Imbert

et al. 2011

Objective To analyse treatment outcomes after SET law enforcement and to evaluate the contribution of cryopreservation in a SET policy. Material Embryo transfer cycles performed after the law enforcement (SET period) was retrospectively compared to the cycles performed before the law enforcement (DET period).Results Pregnancy and delivery rates after fresh transfer of SET and DET periods were comparable (31.7% versus 33.3% and 24.5% versus 26.2%, respectively, NS). Overall twin delivery rate is significantly decreased after the law enforcement (11.3% versus 22.4%, p<0.001) but not in patients aged 36 to 39 years (20.3% versus 24%, NS). Frozen-thawed embryo cycles allowed similar cumulative pregnancy rate (30.6%, NS). Taking into account all frozen embryos still to be transferred, SET period offers a better overall pregnancy rate than the DET period (36.1% versus 32.3%, p<0.01). ConclusionsThe Belgian law allowed a dramatic reduction of twin deliveries especially for patients under 36 years. Cryopreservation maintains a similar cumulative pregnancy rate.