teratozoospermia

Teratozoospermia is a condition in which a large proportion of a man’s sperm have abnormal morphology, meaning the sperm are irregular in shape or structure. It is typically identified through a semen analysis using strict Kruger morphology assessment, which reports the percentage of morphologically normal sperm. Under current criteria, a normal morphology rate of 4% or higher is considered within the normal range; a lower percentage indicates teratozoospermia. The condition can occur alone or with other semen abnormalities such as reduced concentration (oligospermia) or reduced motility (asthenozoospermia).

Causes and associations are diverse. Genetic factors, including chromosomal abnormalities and Y-chromosome microdeletions, can play a role. Acquired factors include varicocele, infections, hormonal imbalances, testicular injury, and prior fever. Environmental and lifestyle exposures—tobacco use, excessive alcohol, illicit drugs, occupational or heat exposure—and certain medications may contribute. Oxidative stress and advanced paternal age have also been linked to abnormal sperm morphology.

Impact and management vary. Teratozoospermia can reduce fertilization potential and affect embryo quality, but natural conception is possible in some cases. Management targets underlying causes and may include lifestyle changes, treatment of infections or hormonal disorders, and, in some instances, antioxidant therapy. For many couples, assisted reproductive technologies such as in vitro fertilization with intracytoplasmic sperm injection (ICSI) are used. In select cases, sperm retrieval methods may be considered if morphology is severely impaired. Diagnosis and treatment decisions are individualized based on overall semen analysis and reproductive goals.