The recent issue of the British Journal of Pharmacology included a study showing that caffeine reduces muscle activity in the Fallopian tubes that carry eggs from a woman’s ovaries to her womb. “Our experiments were conducted in mice, but this finding goes a long way towards explaining why drinking caffeinated drinks can reduce a woman’s chance of becoming pregnant,” says Sean Ward, professor of physiology and cell biology, at the University of Nevada School of Medicine, who conducted the study. It was found that caffeine stops the actions of specialized pacemaker cells in the wall of the tubes. When inhibited, the eggs can’t move down the tubes as effectively.