There are also cultural norms that come into play, including traditional notions of men being the “breadwinners” of the family, said Jamie Ladge, an associate professor of management and organizational development at Northeastern University who studies work-life integration. Unspoken workplace rules discourage fathers from taking full advantage of paternity leave when it’s offered, with more than two-thirds of dads saying they’ve felt the pressure to return from leave as soon as possible, according to a survey from Volvo Car USA and the Harris Poll.