Aspermia is the complete lack of semen (not to be confused with azoospermia, the lack of sperm cells in the semen). It is associated with infertility. One of the causes of aspermia is retrograde ejaculation, which can be brought on by excessive drug use, or as a result of prostate surgery. Another cause of aspermia is ejaculatory duct obstruction,...
Lack of secretion or expulsion of semen following ejaculation. ... (05 Mar 2000) ... 
(ә-spur´me-ә) aspermatogenesis. anejaculation.
Absence of semen.
Type: Term Pronunciation: ā-sper′mē-ă, ă-sper′ Definitions: 1. Lack of secretion or expulsion of semen following ejaculation.
An abnormal condition, affecting fertility, in which a male is completely unable to ejaculate or secrete semen.
aspermia Failure of the formation or the emission of semen.
the failure either to produce or to ejaculate sperm