It's commonly believed that women who live together eventually experience the syncing of their monthly periods. But could it just be chance?
The theory behind the syncing of menstrual cycles is that women's pheromones interact when they are in close proximity, causing them to have their period at the same time. Many females buy into it.
"I definitely think it's true," says Emma. "It would be too much of a coincidence otherwise."
Emma, 24, lived with five girls at university. She says that within a few months they all had their period at the same time.
