RESUMEN
Objective: To date, evidence regarding the effectiveness and safety of two consecutive cycles of single embryo transfer (2SETs) compared with one cycle of double embryo transfer (DET) has been inadequate, particularly considering infertile women with different prognostic factors. This study aimed to comprehensively summarize the evidence by comparing 2SETs with DET. Methods: PubMed, Embase, Cochrane Library databases, ClinicalTrails.gov, and the WHO International Clinical Trials Registry Platform were searched up to March 22, 2022. Peer-reviewed, English-language randomized controlled trials (RCTs) and observational studies (OS) comparing the outcomes of 2SETs with DET in infertile women with their own oocytes and embryos were included. Two authors independently conducted study selection, data extraction, and bias assessment. The Mantel-Haenszel random-effects model was used for pooling RCTs, and a Bayesian design-adjusted model was conducted to synthesize the results from both RCTs and OS. Main Results: Twelve studies were finally included. Compared with the DET, 2SETs were associated with a similar cumulative live birth rate (LBR; 48.24% vs. 48.91%; OR, 0.97; 95% credible interval (CrI), 0.89-1.13, τ2 = 0.1796; four RCTs and six observational studies; 197,968 women) and a notable lower cumulative multiple birth rate (MBR; 0.87% vs. 17.72%; OR, 0.05; 95% CrI, 0.02-0.10, τ2 = 0.1036; four RCTs and five observational studies; 197,804 women). Subgroup analyses revealed a significant increase in cumulative LBR (OR, 1.33; 95% CrI, 1.29-1.38, τ2 = 0) after two consecutive cycles of single blastocyst transfer compared with one cycle of double blastocyst transfer. Moreover, a lower risk of cesarean section, antepartum hemorrhage, preterm birth, low birth weight, and neonatal intensive care unit admission but a higher gestational age at birth and birth weight were found in the 2SETs group. Conclusion: Compared to the DET strategy, 2SETs result in a similar LBR while simultaneously reducing the MBR and improving maternal and neonatal adverse outcomes. The 2SETs strategy appears to be especially beneficial for women aged ≤35 years and for blastocyst transfers.
Asunto(s)
Transferencia de Embrión , Peso al Nacer , Transferencia de Embrión/métodos , Femenino , Humanos , Embarazo , Índice de Embarazo , Transferencia de un Solo EmbriónRESUMEN
RESEARCH QUESTION: How do cumulative live birth rates (CLBR), cumulative multiple live birth rates (CMLBR) and dropout rates over six IVF and intracytoplasmic sperm injection (ICSI) cycles change over time? DESIGN: Prospective longitudinal cohort (nâ¯=â¯16,073 patients; 48,946 cycles) starting a first fresh assisted reproductive technology cycle between 1 January 2014 and 31 December 2016, with follow-up until 31 December 2017. Outcomes between the periods 2014-2017 and 2009-2012 were compared. RESULTS: Conservative estimates of CLBR after six complete cycles were significantly higher in women younger than 35 years after every cycle: one to three, adjusted P-value [p adj] < 0.0001; four, pâ¯=â¯0.01; five, p adjâ¯=â¯0.03; six, p adjâ¯=â¯0.04) and after the first cycle in women aged 35-37 years (p adjâ¯=â¯0.04) in 2014-2017 versus 2009-2012. For an optimal estimate, the CLBR was significantly higher after the first three cycles in women younger than 35 years (all p adj < 0.0001) and after the first cycle in women aged 35-37 years (p adjâ¯=â¯0.04). The CMLBR rate decreased from 5.1% ± 0.19 (SE) to 4.1% ± 0.16 for the conservative estimate and from 8.6% ±0.37 (SE) to 6.7% ± 0.30 for the optimal estimate after six complete cycles for the whole cohort. Dropout rates of complete cycles were 26.5% 29.4%, 33.4%, 38.9% and 47.3% after the first to fifth cycle, respectively. Compared with 2009-2012, the dropout rate in the current period was significantly higher for the first (P < 0.0001) and second (Pâ¯=â¯0.0124) cycle. CONCLUSION: Over six complete IVF/ICSI cycles, CLBR and dropout rates increased and multiple live birth rates decreased when 2014-2017 was compared with 2009-2012.
Asunto(s)
Tasa de Natalidad/tendencias , Pacientes Desistentes del Tratamiento/estadística & datos numéricos , Inyecciones de Esperma Intracitoplasmáticas/tendencias , Femenino , Humanos , Estudios Prospectivos , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricosRESUMEN
STUDY QUESTION: How do the national cumulative (multiple) live birth rates over complete assisted reproduction technology (ART) courses of treatment per woman in Belgium compare to those in other registries? SUMMARY ANSWER: Cumulative live birth rates (CLBRs) remain high with a low cumulative multiple live birth rate when compared with other registries and publications. WHAT IS KNOWN ALREADY: In ART, a reduction in the multiple live birth rate could be achieved by reducing the number of embryos transferred. It has been shown that by doing so, live birth rates per cycle were maintained, particularly when the augmentation effect of attached frozen-thawed cycles was considered. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study included all patients with a Belgian national insurance number who were registered in the national ART registry (Belrap) and who started a first fresh ART cycle between 1 July 2009 until 31 December 2011 with follow up until 31 December 2012. We analysed 12 869 patients and 38 008 cycles (both fresh and attached frozen cycles). PARTICIPANTS, MATERIALS, SETTINGS, METHODS: CLBRs per patient who started a first ART cycle including fresh and consecutive frozen cycles leading to a live birth. Conservative estimates of cumulative live birth assumed that patients who did not return for treatment had no chance of achieving an ART-related live birth, whereas optimal estimates assumed that women discontinuing treatment would have the same chance of achieving a live birth as those continuing treatment. A maximum of six fresh ART cycles with corresponding frozen cycles was investigated and compared with other registries and publications. MAIN RESULTS AND ROLE OF CHANCE: The CLBR was age dependent and declined from 62.9% for women <35 years, to 51.4% for women 35-37 years, to 34.1% for women 38-40 years and 17.7% for women 41-42 years in the conservative analysis after six cycles. In the optimal estimate, the CLBR declined from 85.9% for women <35 years, to 72.0% for women 35-37 years, to 50.4% for women 38-40 years and 36.4% for women 41-42 years. The cumulative multiple live birth rates for the whole population were 5.1 and 8.6% for the conservative and optimal estimate, respectively. LIMITATIONS, REASONS FOR CAUTION: Conservative and optimal estimates use assumptions for the whole ART population and do not take the individual patient into account. WIDER IMPLICATIONS OF THE FINDINGS: These data reinforce the validity of the Belgian model of coupling reimbursement of ART costs to a restriction in the number of embryos transferred. Our data can improve decision-making in medical ART practice both on the patient level and for society at large and could provide health care takers and insurance companies with a valid model. STUDY FUNDING COMPETING INTERESTS: none.