Women's battle for equality is bringing benefits in health, finance and political participation but there could be an ugly side-effect - rising levels of violence against them. Campaigners at Women Deliver, the world's largest conference on women's health and rights in a decade, said many men saw women's increasing empowerment as a threat to their masculinity. "It's something we observe in many parts of the world," said Babatunde Osotimehin, head…