Can what my SO be doing affect his ability to get me pregnant?

My husband and I are trying to baby, we're only on our second month of TTC, but after not getting pregnant this last month I've been thinking... Could something be wrong with his sperm?
​He is an excessive weed smoker, and when I say excessive I mean at least every other day. I have heard that it can affect his sperm count or the sperm speed but I want to hear other people's input off person experience if there is anyone out there. 
​I know I'm able to conceive, as I was pregnant at 16 and terminated it due to my circumstances. 
​My husband on the other hand had multiple year long relationships before me where he had unprotected sex and never got anyone pregnant. Can weed smoking affect his ability to conceive with me?