Cranberry juice does absolutely nothing for a sway. It is not concentrated enough to affect your body and it's just another source of nutrients that if anything may even sway blue. In our stats, not even the cranberry supplements did anything when taken by DW - same results as the overall stats of the site.
Re alcohol - that is up to each individual to decide. I personally think that a drink or two a day, with food, prior to BFP is probably ok, but many people will not be comfortable doing that. Every person decide that for oneself.
