SSRIs can cause problems in spermatogenesis
as you have mentioned. However, in your case, the risk-benefit ratio needs to be assessed regarding whether or not the medication can be discontinued.
This would depend on your husband's psychiatrist's assessment of whether or not it would be advisable for him to be off the drug; plus, if ICSI
is required, then what is the exact sperm number & quality. If it is reasonable, then stopping the drug may be more harmful than continuing the medication and proceeding with IVF/ICSI