Being on AAS will making getting a woman pregnant harder, but NOT impossible at all. It does NOT make men sterile, not even for a second. It does reduce sperm count - hence, why it is is harder to get a woman pregnant. But it is still possible.
There will be NO impact to the fetus if the MAN is taking AAS. If the WOMAN is taking AAS there will likely be problems.
There will be NO impact to the fetus if the MAN is taking AAS. If the WOMAN is taking AAS there will likely be problems.