biostudies-literatureWong KMThe Netherlands Organisation for Health Research and DevelopmentZonMw998-1006https://www.ebi.ac.uk/biostudies/studies/S-EPMC7970725biostudies-literatureUnknown36(4)<h4>Study question</h4>Is IVF with frozen-thawed blastocyst transfer (freeze-all strategy) more effective than IVF with fresh and frozen-thawed blastocyst transfer (conventional strategy)?<h4>Summary answer</h4>The freeze-all strategy was inferior to the conventional strategy in terms of cumulative ongoing pregnancy rate per woman.<h4>What is known already</h4>IVF without transfer of fresh embryos, thus with frozen-thawed embryo transfer only (freeze-all strategy), is increasingly being used in clinical practice because of a presumed benefit. It is still unknown whether this new IVF strategy increases IVF efficacy.<h4>Study design, size, duration</h4>A single-centre, open label, two arm, parallel group, randomised controlled superiority trial was conducted. The trial was conducted between Human reproduction (Oxford, England)Transfer of fresh or frozen embryos: a randomised controlled trial.PMC7970725171101007Mol Fvan der Veen FWong KMRepping SKaaijk EMVerhoeve HRvan Wely MMastenbroek SfalseTransfer of fresh or frozen embryos: a randomised controlled trial.<h4>Study question</h4>Is IVF with frozen-thawed blastocyst transfer (freeze-all strategy) more effective than IVF with fresh and frozen-thawed blastocyst transfer (conventional strategy)?<h4>Summary answer</h4>The freeze-all strategy was inferior to the conventional strategy in terms of cumulative ongoing pregnancy rate per woman.<h4>What is known already</h4>IVF without transfer of fresh embryos, thus with frozen-thawed embryo transfer only (freeze-all strategy), is increasingly being used in clinical practice because of a presumed benefit. It is still unknown whether this new IVF strategy increases IVF efficacy.<h4>Study design, size, duration</h4>A single-centre, open label, two arm, parallel group, randomised controlled superiority trial was conducted. The trial was conducted between 2021-01-01T00:00:00Z2021 Mar2025-04-21T23:37:02.94Z2025-04-05T19:12:35.939ZS-EPMC79707253373436910.1093/humrep/deaa305