The Oregon state legislature mandated that any employer with five or more employees grant a paid six-month maternity leave to any woman who gave birth while on the company's payroll. The legislature imposed no requirements regarding paid or unpaid family leave for men who had just had a child. In deciding to enact the measure, the legislators relied principally on evidence that various rising social problems, such as drugs and crime, were caused in part by the rise in working women and a consequent failure of mothers to bond with their infants. Frank, the father of a newborn infant who wished to have a paid paternity leave, has challenged the statute on the grounds that it violates his equal protection rights. Will Frank's challenge succeed?