More than 90% of male infertility or sterility cases are caused by sperm abnormalities, including poor sperm quality, low sperm count, abnormal morphology, or a combination between all of them. Other causes that can affect a man's fertility are: anatomical problems, genetic defects, hormonal imbalances, etc.
See also: Male infertility: causes, symptoms, treatment and statistics.
Read the full article on: Male Fertility Testing – How Do You Know if You Are Infertile? ( 69).
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Sara Salgado
B.Sc., M.Sc.
Embryologist
Degree in Biochemistry and Molecular Biology from the University of the Basque Country (UPV/EHU). Master's Degree in Human Assisted Reproduction from the Complutense University of Madrid (UCM). Certificate of University Expert in Genetic Diagnosis Techniques from the University of Valencia (UV).