"[M]en with a childhood history of diarrhea showed a distinctive preference for highly feminized female faces..."

"... by contrast, they betrayed no bias at all when asked to evaluate the faces of other men. Since you can’t inseminate another male—believe me, I’ve tried—that makes sense. The inverted pattern appeared for ladies with a childhood history of diarrhea: unlike their peers who preferred male faces with androgynous features, women who’d spent a worrisome amount of time on the toilet as little girls now liked their men, or at least their men’s faces, as manly as possible. Similarly, they showed no particular bias when it came to what makes a woman’s face attractive."

From a Scientific American item titled "This Queasy Love: How Having Frequent Diarrhea as a Child Shapes Your Adult Mate Choice," by Jesse Bering.