Transfer of a poor-quality along with a good-quality embryo on in vitro fertilization/intracytoplasmic sperm injection-embryo transfer clinical outcomes: a systematic review and meta-analysis.

OBJECTIVE: To investigate the effect on the pregnancy rate of transfer of a good-quality embryo (GQE) and a poor-quality embryo (PQE) in comparison with a single GQE transfer. DESIGN: Systematic review and meta-analysis. SETTING: Not applicable. PATIENT(S): Infertility patients undergoing in vitro fertilization/intracytoplasmic sperm injection- embryo transfer. INTERVENTION(S): Three major electronic databases (PubMed, Embase, and Cochrane Library) for studies those compared single GQE transfer to double embryo transfer of a GQE + PQE were searched. The Newcastle-Ottawa Quality Assessment Scale was used to evaluate the study quality. Random-effect meta-analysis was performed on all data for an overall analysis, followed by a subgroup analysis (fresh cleavage-stage embryos, fresh blastocysts, frozen-thawed blastocysts, and the same assessment criteria for blastocyst quality). MAIN OUTCOME MEASURE(S): The primary outcome was clinical pregnancy rate (CPR). RESULT(S): A total of 17 studies with 17,612 cycles for GQE transfer and 6,431 cycles for GQE + PQE transfer were included in the meta-analysis. No significant differences were found in CPR (relative risk [RR] = 1.02; 95% confidence interval [CI], 0.91-1.14) and live birth rate (RR = 0.96; 95% CI, 0.87-1.07) between GQE + PQE and GQE transfers. However, the transfer of GQE + PQE increased multiple pregnancy rate (RR = 0.14; 95% CI, 0.09-0.20) and multiple birth rate (RR = 0.08; 95% CI, 0.06-0.12), when compared with the patients undergoing a single GQE transfer. Subgroup analyses by type of embryo for transfer and assessment criteria for embryo quality showed similar trends. CONCLUSION(S): Double embryo transfer with GQE + PQE does not result in increased or decreased CPR and live birth rate when compared with a single GQE transfer but leads to a higher multiple pregnancy rate and multiple birth rate. CLINICAL TRIAL REGISTRATION NUMBER: Prospero CRD42022296681 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=296681) registered on January 7, 2022.