Sexes: The Hidden Power of Body Odors

Women who work or live together tend to get their menstrual cycles in sync. That curious phenomenon, known for years by scientists and many ordinary folk, has long been suspected as an indication that humans, like insects and some mammals, communicate subtly by sexual aromas known as pheromones. Last week Philadelphia researchers weighed in with two reports showing that scents, including underarm odors, do indeed affect menstrual cycles.

The reports came with a kicker: male scents play a role in maintaining the health of women, particularly the health of the female reproductive system. Researchers at the Monell Chemical Senses Center and...