An estimated 43 million American workers have no access to paid leave. They’re mostly low-wage workers, already strained when recovering after the birth of a child, for example, or tending to a sick kid. Top earners, on the other hand, tend to receive the benefits through employers, according to a recent survey by the Bureau of Labor Statistics .

The problem compounds for single mothers who lack the benefits. Some economists argue closing the wage gap would lift nearly half out of poverty, according to a report from the Institute for Women’s Policy Research.