RESUMO
PURPOSE: Increasing the number of transferred blastocysts sometimes is selected for patients with repeated implantation failure (RIF). To confirm this strategy, the pregnancy rates (PRs) were compared among the groups who had transferred either a single morphologically good blastocyst (MGB group), double blastocysts with both a MGB and a morphologically poor blastocyst (MGB + MPB group), or a double-BT with 2 MGBs (two-MGB group). METHODS: This study was performed between April, 2009 and September, 2014, including 634 cycles for 354 patients with RIF. All the patients received cryopreserved blastocysts in either hormone replacement or natural ovulatory cycles. The included MGBs were at more than the Gardner grade 3BB stage. The PR and implantation rates (IRs) among the three groups were statistically evaluated by the chi-square test. Statistical significance was set at P < .01. RESULTS: Although the PRs were similar in these three groups, the IR in the MGB + MPB group was significantly lower than that of the MGB group. The rate in the two-MGB group also was significantly lower than that of the MGB group. CONCLUSION: A double-BT with a MGB and a MPB does not increase the pregnancy rate, compared with a single-BT with a MGB among patients with RIF.