I don't think it affects your sperm . . . it wouldn't hurt to ask your doc, tho.
Street drugs obviously affect sperm count and viability and longevity. Layman terms... street drugs can make sperm count go down, cause sperm to be defective and not live long. But you need to ask a pharmacist (as they would know better than a doc) as every drug is different.
I found the following info on oxycodone. It says you shouldn't even be taking it for long periods of time. It's an addictive drug that is easy to abuse.
If you cannot find anything on the affects this drug has on sperm, then you should ask your doctor for a different drug to help you that will also help you to conceive. Honestly, you guys probably just aren't trying to conceive correctly. Does she check her temperature every morning or check for cervical changes and discharge or does she use ovulation prediction kits?
She can't blame it all on you. She's probably just frustrated and feeling like a failure. It is hard for a woman when she can't conceive when she wants. Tell her to get on here and speak with us! We'll all be glad to offer help and support to her too.
My fiancee was taking Oxycttons and I was taking percocets when I became pregnant with twins, so I really do not think it effects sperm at all. As far as birth defects, well I had to keep taking percocet during my entire pregnancy due to back problems and both of my babies were born and still are happy and healthy.