Me and my boyfriend are trying to conceive, but he is taking methadone will that cause problems with us trying to conceive?

Fertility and meds: It should not directly affect sperm count however it would be important to get a semen analysis to check his baseline count. However, medications like Methadone can have an affect on performance.

Possibly: Opiates cause infertility by decreasing testosterone in men. If he just started taking the Methadone then fertility will improve some over time. But Methadone does contribute to low testosterone as well as opiates, so it does not help. He needs the methadone. He needs an addiction doctor to help him to not make the Methadone a permanent part of his life.