<strong>Study Question:</strong> The question: is there any difference in pregnancy rate between embryo transfer day 5 and day 6 in IVF? What Is Known Already? Blastocyst transfer is increasingly popular in assisted reproductive technology (ART) centers today. Very few articles concentrate on comparing Day 5 and Day 6 embryo transfer with conflict results. <strong>Objective, Study Design:</strong> Systematic review and meta-analysis of published controlled studies. Searches conducted from 2001-2020 on PubMed. Medline, EMBASE, and ISI Web of Science Electronic database is used to collect data, using the following search terms: blastocyst, Day 5, Day 6, embryo transfer (E.T.) and pregnancy rate. <strong>Materials, Setting, Methods:</strong> A total of 6 full-text articles preselected from 211 references, based on title and abstract. Two independent reviewers performed data selection and extraction according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement (PRISMA). This systematic review was conducted according to (PICO) standard. Random-effect meta-analysis performed on all data (overall analysis). <strong>Results and the Role of Chance:</strong> Data from 6 relevant articles were extracted and integrated into the meta-analysis that reported clinical pregnancy rate (CPR) as an outcome in 5640 cycles, 2274 cycle had embryo transfer at day 6 and the control was 3366 cycle had embryo transfer day 5 showed a significantly higher clinical pregnancy rate following Day 5 embryo transfer compared with Day 6 embryo transfer with odd ratio and 95% confidence limit 0.73 (0.66 - 0.82)<em> p</em> value < 0.000. Sensitivity analysis led to similar results and conclusions.<strong> Limitations, Reasons for Caution: </strong>The validity of meta-analysis results depends mainly on the quality and the number of published studies available. Indeed, this meta-analysis included no randomized controlled trial (RCT). <strong>Wider Implications of the Findings: </strong>In regards to the results of this