It shouldn't matter much what the men were drinking around the time of conception because sperm are formed THREE MONTHS BEFORE conception.
During delivery OTOH, he can drink as much as he wants!
Also:
With some women and men, their partners need to drink for there to be a conception period!
I'm not sure the 3 months figure is accurate, but at any rate, regardless of when they are formed, if they are drenched in alcohol at the time they are used for fertilization, it's not much of a stretch to think there could be an effect on embryo development. Read up on the history of IVF and the solutions used to grow embryos in -- tiny changes in the chemistry of the solutions has a huge effect on embryo survival rates even just to the 4 and 8 cell stages.