Well, pretty much anything you do can influence your epigenome, which is passed on to your offspring. But this includes the air you breathe, where you live, your lifestyle, your diet, any drugs or meds you take, etc...
But I've never seen any evidence (or even reasonable claims) suggesting that AAS or the ancillaries we use increase the risk of birth defects, especially once they are no longer active in your system (because AAS very well can cause birth defects in pregnant women if they use while pregnant).
The one drug some of us use that I'd advise you to stay away from is accutane. This stuff is an extremely well documented mutagen and has a VERY high risk of causing birth defects if present in the system of the female (and I believe male, as well) at time of conception or during pregnancy. The same goes for Finasteride and Dutasteride, come to think of it.
To be safe, just avoid using any SERMs or other ancillaries within 2 months of attempting conception. Testosterone is fine (and likely all AAS), but it will decrease your sperm count and motility.
For anyone else interested in having kids, do some research on epigenomes. This is a HUGE emerging subject in the field of genetics, and flips over most of what we once thought we knew about genetic inheritance. Turns out that a record of just about EVERYTHING you are exposed to in your lifetime is passed on to your offspring (though it doesn't hold as much weight as your genome. or the genes you yourself received that cannot be changed).
http://en.wikipedia.org/wiki/Epigenome