Post-testicular factors decline male fertility due to conditions that affect the male genital system after testicular sperm production and take account of defects of the genital tract as well as problems in ejaculation: Vas deferens obstruction Lack of Vas deferens, often connected to genetic markers for Cystic Fibrosis, Infection, e.g. prostatitis, retrograde ejaculation, Ejaculatory duct obstruction, Hypospadias, Impotence. A journal is a periodical publication intended to further progress of science, usually by reporting new research. Most journals are highly specialized, although some of the oldest journals publish articles, reviews, editorials, short communications, letters, and scientific papers across a wide range of scientific fields.