abnormal vas deferens morphology absent vas deferens MP:0003556 MP:0003557 MPheno.ontology absence of the secretory duct of the testicle that carries spermatozoa, running from the epididymis, of which it is the continuation, to the prostatic urethra where it terminates to form ejaculatory duct absent ductus deferens agenesis of vas deferens ductus deferens aplasia vas deferens aplasia