Meta-analysis comparing “freeze-all strategy” with traditional cycle of in vitro fertilization and fresh embryo transfer
Diego Mendes Do Carmo, Eduardo Camelo de Castro, Amanda Rincon Godinho, Antônio Márcio Teodoro Cordeiro Silva
Objective: To perform a meta-analysis comparing the outcomes of the freeze-all strategy with traditional cycles of in vitro fertilization and fresh embryo transfer. Methods: We used the Pubmed, EMBASE and Cochrane virtual databases, and used descriptors such as Assisted Reproductive Techniques, Fresh embryo transfer, Frozen-thawed embryo transfer, Freeze-all embryo transfer. Quality randomized controlled trials comparing transfer techniques were included. The variables of interest analyzed were the rates of pregnancy, clinical pregnancy, ongoing pregnancy and abortion, with each study containing at least one of these. Results: Five studies were selected. For rates of clinical pregnancy and ongoing pregnancy, there was greater success for the freeze-all strategy. There was no statistical difference for the rate of chemical pregnancy. The abortion rate had in the transfer of frozen a protective factor. Conclusions: Among the analyzed variables, it was indicated that the freeze-all strategy stands out. This leads us to a direction that the freezing techniques have already reached a level where we can, fearless, wait for a next cycle, that is more physiological and that the technique is better tolerated by the female organism.
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