"In a study of almost 350 young men, sperm levels were a third lower in those whose mothers had drunk more than four drinks a week during pregnancy compared with teetotalers."
Meanwhile, would-be moms-to-be, lay off the bacon-wrapped whatevers: The BBC also reports that "overweight women undergoing fertility treatment have double the risk of miscarriage of normal weight women."
By the way, even if you should see one hoisting a tipple, it's not polite to tell a pregnant woman to stop drinking.
Image source: Flickr member BluEyedA73 under Creative Commons