The present study analysed live birth ratios in frozen embryo transfer (FET) cycles where embryo ploidy status was determined with preimplantation genetic testing (PGT) using next-generation sequencing (NGS). PGT was performed on trophectoderm cells biopsied at the blastocyst stage. The present prospective cohort study included 112 women undergoing frozen embryo transfer, with NGS PGT. The control group consisted of 85 patients who underwent the IVF procedure with FET planned for a subsequent cycle. The live birth rate per cycle was higher by ~18.5 percentage points in the investigated compared with control group (42.0% vs 23.5% respectively; P=0.012). The differences between the study and control groups were also significant for clinical pregnancy (42.0% vs 23.5% respectively; P=0.012), implantation (41.2% vs 22.2% respectively; P=0.001) and pregnancy loss rates (9.6% vs 28.6% respectively; P=0.027). The results show that PGT NGS is a useful method for embryo selection and it may be implemented in routine clinical practice with propitious results.