There is very little evidence of any harmful effect on male fertility from steroids used therapeutically but if there is any effect it may depend upon the length of time that these are taken for and their dose. This is not the case when anabolic steroids are used recreationally where there is direct evidence of suppression of sperm production, which can be irreversible. I would suggest that you get a semen analysis done to see whether sperm production is going on and then ask for a referral to a fertility expert with an interest in male factor problems who will probably want to run some further tests dependent upon what your semen analysis shows.