RESUMO
OBJECTIVE: To explore the correlation of the sperm DNA fragmentation index (DFI) with age and other semen parameters in infertile men and its influence on the outcomes of in vitro fertilization and embryo transplantation (IVF-ET). METHODS: Semen samples were obtained from 6 162 infertile males in our hospital between July 2017 and December 2018. Sperm concentration, the percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS) and sperm DFI were determined by computer-assisted semen analysis, modified Papanicolaou staining and sperm chromatin structure assay, respectively. According to the sperm DFI, the samples were divided into three groups: DFI≤15%, 15%