A new study finds that working parents, who believe in sharing child-care duties equally, rarely do it. One reason: women enjoy it more than men, The Wall Street Journal says.  Researchers surveyed 181 married professors with kids under age two, all of whom had access to paid parental leave. The majority of male and female professors said they think parents should share child care duties. But only three of 109 menreported that they did half or more of the care, while 70 of 73 women reported doing at least half, even when both spouses worked full time. Female professors on paid maternity leave spent most of their time off on infant care, including breastfeeding. Male professors used leaves to focus on research and publishing papers.