last time smoking..

So I'm going in with my OBGYN too see what's wrong with me next Thursday. I had 2 previous miscarriages. The last one was June. Ever since then I'd had irregular period, either 40-46 days. I've been smoking weed a few times already because I wanted to take some time off and wait for my body to heal from the miscarriages. We haven't been planning but we don't prevent it. Is it okay if I smoke one last time before ttc again? Keep in mind that I'm going for some test next Thursday. Please comment.