Will my husband's medication affect a developing fetus while trying to conceive?
Due to the lack of available information, it may be best to wait on attempting to conceive until after the drugs are out of his system. When a clinical study on a medication is conducted, the amount of drug that goes into the semen and the drug's effect on sperm is not typically evaluated. Assuming your husband has normal kidney and liver function, this should occur approximately three days after his last dose of medicine for most medications. However, as in all cases concerning important medical decisions, it is best to speak to your physician to discuss your personal situation and decide what is best for you, your husband, and your future child.
There are also ethical concerns regarding testing medications on pregnant women. For this reason, when they are brought to market, most drugs do not have clear data on the effect they may or may not have on a pregnancy or developing fetus. It is after these medications have been available that further pregnancy studies may be conducted.
There is no data to support that medications used by the father prior to conception will affect the baby in any way. There is, however, some limited data to show that it may decrease the chances for the couple to become pregnant.