We don't know, altho it is def. fun to speculate about. Personally I don't think there's much of a difference between X and Y sperm, because for most of their development, they are actually just one big sperm wearing the exact same skin, and what affects one, would then affect the other as well. They actually don't even divide until quite far along in their formation.
My daughter was from swaying, my sister's daughter she didn't sway (she actually wanted another boy I think), but had been having horrible gall bladder problems for 4 years and gone from 180 lbs to 110 and had her gall bladder removed 3 months before she got pg with her daughter. The other two were cousins and not even related to one another and one is not related to any of us genetically. I don't think they swayed, at least not to my knowledge. :) I try to keep my xtracurricular activities out of my family LOL!!!