“I don’t have ADHD, but I know that women who do are advised to stop meds during pregnancy. Should my husband stop taking his stimulant while we’re trying to get pregnant?”
There are no data on men who are taking an ADHD medication at the time of conception. The most conservative approach would be for him to stay off his medication while you are trying to conceive.
If he’s taking a short-acting drug, he could still take it during the day (assuming he needs it for work), and simply skip his evening dose, if that’s when you have sex.