The sperm cells begin to have abnormal shapes, and are fewer in number. If abuse continues long enough, the male becomes infertile. The testes of male athletes who have been stacking and cycling steroids for years decrease in size. If the adult male stops taking anabolic steroids, testicular function will probably return to normal. However, it may take four months to a year or more for him to regain normal sperm cell shape and fertility.

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The sperm cells begin to have abnormal shapes, and are fewer in number. If abuse continues long enough, the male becomes infertile. The testes of male athletes who have been stacking and cycling steroids for years decrease in size. If the adult male stops taking anabolic steroids, testicular function will probably return to normal. However, it may take four months to a year or more for him to regain normal sperm cell shape and fertility.

The purpose of this study was to assess the influence of the administration of high doses of androgenic anabolic steroids (AAS) on endocrine and semen parameters. Thirty volunteering bodybuilders were studied (ages ranging between 26.6 +/- 4.1 years). A history of anabolic steroid administration was recorded for fifteen subjects, and results of semen analysis and endocrine parameters were compared with data from fifteen bodybuilders not using steroids. In those subjects using AAS, eight had sperm counts under the lower normal limit (20 x 10(6) sperm/ml), three had azoospermia, two polyzoospermia, and two had normal sperm counts. The percentage of morphologically normal sperm was significantly reduced, only 17.7% had normal spermatozoa. In the control group, only one subject had oligozoospermia.
http://0-www.ncbi.nlm.nih.gov....

There really haven't been enough studies in this area.

If he was using them at the time of conception it could have an effect but it depends on how much and how often he uses them, also which steriods he uses will result in diffrent effects, if you want to find out more then email me at joe.fathers@googlemail.com

i have read the previous answer and he is correct in what he has said, but having read many investigations into this matter, the reason i have done t...

If he was using them at the time of conception it could have an effect but it depends on how much and how often he uses them, also which steriods he uses will result in diffrent effects, if you want to find out more then email me at joe.fathers@googlemail.com

i have read the previous answer and he is correct in what he has said, but having read many investigations into this matter, the reason i have done this is because my cousin is in charge of experiments into steroid impacts on the body...